diff --git a/src/main/java/org/icatproject/ids/DfInfoImpl.java b/src/main/java/org/icatproject/ids/DfInfoImpl.java
deleted file mode 100644
index 214d6aba..00000000
--- a/src/main/java/org/icatproject/ids/DfInfoImpl.java
+++ /dev/null
@@ -1,89 +0,0 @@
-package org.icatproject.ids;
-
-import org.icatproject.ids.plugin.DfInfo;
-
-public class DfInfoImpl implements DfInfo, Comparable<DfInfoImpl> {
-
-    private String createId;
-
-    private long dfId;
-
-    private String dfLocation;
-
-    private String dfName;
-
-    private long dsId;
-
-    private String modId;
-
-    public DfInfoImpl(long dfId, String dfName, String dfLocation, String createId, String modId, long dsId) {
-        this.dfId = dfId;
-        this.dfName = dfName;
-        this.dfLocation = dfLocation;
-        this.createId = createId;
-        this.modId = modId;
-        this.dsId = dsId;
-    }
-
-    @Override
-    public boolean equals(Object obj) {
-        if (obj == this) {
-            return true;
-        }
-        if (obj == null || obj.getClass() != this.getClass()) {
-            return false;
-        }
-        return dfId == ((DfInfoImpl) obj).getDfId();
-    }
-
-    @Override
-    public String getCreateId() {
-        return createId;
-    }
-
-    @Override
-    public Long getDfId() {
-        return dfId;
-    }
-
-    @Override
-    public String getDfLocation() {
-        return dfLocation;
-    }
-
-    @Override
-    public String getDfName() {
-        return dfName;
-    }
-
-    public long getDsId() {
-        return dsId;
-    }
-
-    @Override
-    public String getModId() {
-        return modId;
-    }
-
-    @Override
-    public int hashCode() {
-        return (int) (dfId ^ (dfId >>> 32));
-    }
-
-    @Override
-    public String toString() {
-        return dfLocation;
-    }
-
-    @Override
-    public int compareTo(DfInfoImpl o) {
-        if (dfId > o.getDfId()) {
-            return 1;
-        }
-        if (dfId < o.getDfId()) {
-            return -1;
-        }
-        return 0;
-    }
-
-}
diff --git a/src/main/java/org/icatproject/ids/DsInfoImpl.java b/src/main/java/org/icatproject/ids/DsInfoImpl.java
deleted file mode 100644
index 08bd21d0..00000000
--- a/src/main/java/org/icatproject/ids/DsInfoImpl.java
+++ /dev/null
@@ -1,123 +0,0 @@
-package org.icatproject.ids;
-
-import org.icatproject.Dataset;
-import org.icatproject.Facility;
-import org.icatproject.Investigation;
-import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
-import org.icatproject.ids.plugin.DsInfo;
-
-public class DsInfoImpl implements DsInfo {
-
-    private long dsId;
-
-    private String dsName;
-
-    private long facilityId;
-
-    private String facilityName;
-
-    private long invId;
-
-    private String invName;
-
-    private String visitId;
-
-    private String dsLocation;
-
-    public DsInfoImpl(Dataset ds) throws InsufficientPrivilegesException {
-        Investigation investigation = ds.getInvestigation();
-        if (investigation == null) {
-            throw new InsufficientPrivilegesException(
-                    "Probably not able to read Investigation for dataset id " + ds.getId());
-        }
-        Facility facility = investigation.getFacility();
-        if (facility == null) {
-            throw new InsufficientPrivilegesException(
-                    "Probably not able to read Facility for investigation id "
-                            + investigation.getId());
-        }
-        dsId = ds.getId();
-        dsName = ds.getName();
-        dsLocation = ds.getLocation();
-        invId = investigation.getId();
-        invName = investigation.getName();
-        visitId = investigation.getVisitId();
-        facilityId = facility.getId();
-        facilityName = facility.getName();
-    }
-
-    public DsInfoImpl(long dsId, String dsName, String dsLocation, long invId, String invName,
-                      String visitId, long facilityId, String facilityName) {
-        this.dsId = dsId;
-        this.dsName = dsName;
-        this.dsLocation = dsLocation;
-        this.invId = invId;
-        this.invName = invName;
-        this.visitId = visitId;
-        this.facilityId = facilityId;
-        this.facilityName = facilityName;
-    }
-
-    @Override
-    public boolean equals(Object obj) {
-        if (obj == this) {
-            return true;
-        }
-        if (obj == null || obj.getClass() != this.getClass()) {
-            return false;
-        }
-        return dsId == ((DsInfoImpl) obj).getDsId();
-    }
-
-    @Override
-    public Long getDsId() {
-        return dsId;
-    }
-
-    @Override
-    public String getDsName() {
-        return dsName;
-    }
-
-    @Override
-    public Long getFacilityId() {
-        return facilityId;
-    }
-
-    @Override
-    public String getFacilityName() {
-        return facilityName;
-    }
-
-    @Override
-    public Long getInvId() {
-        return invId;
-    }
-
-    @Override
-    public String getInvName() {
-        return invName;
-    }
-
-    @Override
-    public String getVisitId() {
-        return visitId;
-    }
-
-    @Override
-    public int hashCode() {
-        return (int) (dsId ^ (dsId >>> 32));
-    }
-
-    @Override
-    public String toString() {
-        return invId + "/" + dsId + " (" + facilityName + "/" + invName + "/" + visitId + "/"
-                + dsName + ")";
-    }
-
-    @Override
-    public String getDsLocation() {
-        return dsLocation;
-    }
-
-}
diff --git a/src/main/java/org/icatproject/ids/FiniteStateMachine.java b/src/main/java/org/icatproject/ids/FiniteStateMachine.java
deleted file mode 100644
index 84894e33..00000000
--- a/src/main/java/org/icatproject/ids/FiniteStateMachine.java
+++ /dev/null
@@ -1,633 +0,0 @@
-package org.icatproject.ids;
-
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.nio.file.FileAlreadyExistsException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Set;
-import java.util.Timer;
-import java.util.TimerTask;
-import java.util.concurrent.ConcurrentHashMap;
-
-import jakarta.annotation.PostConstruct;
-import jakarta.annotation.PreDestroy;
-import jakarta.ejb.DependsOn;
-import jakarta.ejb.EJB;
-import jakarta.ejb.Singleton;
-import jakarta.json.Json;
-import jakarta.json.stream.JsonGenerator;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import org.icatproject.Dataset;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.LockManager.LockInfo;
-import org.icatproject.ids.LockManager.LockType;
-import org.icatproject.ids.exceptions.InternalException;
-import org.icatproject.ids.plugin.AlreadyLockedException;
-import org.icatproject.ids.plugin.DfInfo;
-import org.icatproject.ids.plugin.DsInfo;
-import org.icatproject.ids.thread.DfArchiver;
-import org.icatproject.ids.thread.DfDeleter;
-import org.icatproject.ids.thread.DfRestorer;
-import org.icatproject.ids.thread.DfWriter;
-import org.icatproject.ids.thread.DsArchiver;
-import org.icatproject.ids.thread.DsRestorer;
-import org.icatproject.ids.thread.DsWriter;
-
-@Singleton
-@DependsOn({"LockManager"})
-public class FiniteStateMachine {
-
-    private class DfProcessQueue extends TimerTask {
-
-        @Override
-        public void run() {
-            try {
-                synchronized (deferredDfOpsQueue) {
-                    if (processOpsTime != null && System.currentTimeMillis() > processOpsTime && !deferredDfOpsQueue.isEmpty()) {
-                        processOpsTime = null;
-                        logger.debug("deferredDfOpsQueue has " + deferredDfOpsQueue.size() + " entries");
-                        List<DfInfo> writes = new ArrayList<>();
-                        List<DfInfo> archives = new ArrayList<>();
-                        List<DfInfo> restores = new ArrayList<>();
-                        List<DfInfo> deletes = new ArrayList<>();
-                        Map<Long, Lock> writeLocks = new HashMap<>();
-                        Map<Long, Lock> archiveLocks = new HashMap<>();
-                        Map<Long, Lock> restoreLocks = new HashMap<>();
-                        Map<Long, Lock> deleteLocks = new HashMap<>();
-
-                        Map<DfInfoImpl, RequestedState> newOps = new HashMap<>();
-                        final Iterator<Entry<DfInfoImpl, RequestedState>> it = deferredDfOpsQueue.entrySet().iterator();
-                        while (it.hasNext()) {
-                            Entry<DfInfoImpl, RequestedState> opEntry = it.next();
-                            DfInfoImpl dfInfo = opEntry.getKey();
-                            Long dsId = dfInfo.getDsId();
-                            DsInfo dsInfo;
-                            try {
-                                Dataset ds = (Dataset) reader.get("Dataset ds INCLUDE ds.investigation.facility", dsId);
-                                dsInfo = new DsInfoImpl(ds);
-                            } catch (Exception e) {
-                                logger.error("Could not get dsInfo {}: {}.", dsId, e.getMessage());
-                                continue;
-                            }
-                            if (!dfChanging.containsKey(dfInfo)) {
-                                final RequestedState state = opEntry.getValue();
-                                logger.debug(dfInfo + " " + state);
-                                if (state == RequestedState.WRITE_REQUESTED) {
-                                    if (!writeLocks.containsKey(dsId)) {
-                                        try {
-                                            writeLocks.put(dsId, lockManager.lock(dsInfo, LockType.SHARED));
-                                        } catch (AlreadyLockedException e) {
-                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
-                                            continue;
-                                        } catch (IOException e) {
-                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
-                                            continue;
-                                        }
-                                    }
-                                    it.remove();
-                                    dfChanging.put(dfInfo, state);
-                                    writes.add(dfInfo);
-                                } else if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
-                                    if (!writeLocks.containsKey(dsId)) {
-                                        try {
-                                            writeLocks.put(dsId, lockManager.lock(dsInfo, LockType.SHARED));
-                                        } catch (AlreadyLockedException e) {
-                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
-                                            continue;
-                                        } catch (IOException e) {
-                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
-                                            continue;
-                                        }
-                                    }
-                                    it.remove();
-                                    dfChanging.put(dfInfo, RequestedState.WRITE_REQUESTED);
-                                    writes.add(dfInfo);
-                                    newOps.put(dfInfo, RequestedState.ARCHIVE_REQUESTED);
-                                } else if (state == RequestedState.ARCHIVE_REQUESTED) {
-                                    if (!archiveLocks.containsKey(dsId)) {
-                                        try {
-                                            archiveLocks.put(dsId, lockManager.lock(dsInfo, LockType.EXCLUSIVE));
-                                        } catch (AlreadyLockedException e) {
-                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
-                                            continue;
-                                        } catch (IOException e) {
-                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
-                                            continue;
-                                        }
-                                    }
-                                    it.remove();
-                                    dfChanging.put(dfInfo, state);
-                                    archives.add(dfInfo);
-                                } else if (state == RequestedState.RESTORE_REQUESTED) {
-                                    if (!restoreLocks.containsKey(dsId)) {
-                                        try {
-                                            restoreLocks.put(dsId, lockManager.lock(dsInfo, LockType.EXCLUSIVE));
-                                        } catch (AlreadyLockedException e) {
-                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
-                                            continue;
-                                        } catch (IOException e) {
-                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
-                                            continue;
-                                        }
-                                    }
-                                    it.remove();
-                                    dfChanging.put(dfInfo, state);
-                                    restores.add(dfInfo);
-                                } else if (state == RequestedState.DELETE_REQUESTED) {
-                                    if (!deleteLocks.containsKey(dsId)) {
-                                        try {
-                                            deleteLocks.put(dsId, lockManager.lock(dsInfo, LockType.EXCLUSIVE));
-                                        } catch (AlreadyLockedException e) {
-                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
-                                            continue;
-                                        } catch (IOException e) {
-                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
-                                            continue;
-                                        }
-                                    }
-                                    it.remove();
-                                    dfChanging.put(dfInfo, state);
-                                    deletes.add(dfInfo);
-                                } else {
-                                    throw new AssertionError("Impossible state");
-                                }
-                            }
-                        }
-                        if (!newOps.isEmpty()) {
-                            deferredDfOpsQueue.putAll(newOps);
-                            logger.debug("Adding {} operations to be scheduled next time round", newOps.size());
-                        }
-                        if (!deferredDfOpsQueue.isEmpty()) {
-                            processOpsTime = 0L;
-                        }
-                        if (!writes.isEmpty()) {
-                            logger.debug("Launch thread to process " + writes.size() + " writes");
-                            Thread w = new Thread(new DfWriter(writes, propertyHandler, FiniteStateMachine.this, writeLocks.values()));
-                            w.start();
-                        }
-                        if (!archives.isEmpty()) {
-                            logger.debug("Launch thread to process " + archives.size() + " archives");
-                            Thread w = new Thread(new DfArchiver(archives, propertyHandler, FiniteStateMachine.this, archiveLocks.values()));
-                            w.start();
-                        }
-                        if (!restores.isEmpty()) {
-                            logger.debug("Launch thread to process " + restores.size() + " restores");
-                            Thread w = new Thread(new DfRestorer(restores, propertyHandler, FiniteStateMachine.this, restoreLocks.values()));
-                            w.start();
-                        }
-                        if (!deletes.isEmpty()) {
-                            logger.debug("Launch thread to process " + deletes.size() + " deletes");
-                            Thread w = new Thread(new DfDeleter(deletes, propertyHandler, FiniteStateMachine.this, deleteLocks.values()));
-                            w.start();
-                        }
-                    }
-                }
-            } finally {
-                timer.schedule(new DfProcessQueue(), processQueueIntervalMillis);
-            }
-
-        }
-
-    }
-
-    private class DsProcessQueue extends TimerTask {
-
-        @Override
-        public void run() {
-            try {
-                synchronized (deferredDsOpsQueue) {
-                    final long now = System.currentTimeMillis();
-                    Map<DsInfo, RequestedState> newOps = new HashMap<>();
-                    final Iterator<Entry<DsInfo, RequestedState>> it = deferredDsOpsQueue.entrySet().iterator();
-                    while (it.hasNext()) {
-                        final Entry<DsInfo, RequestedState> opEntry = it.next();
-                        final DsInfo dsInfo = opEntry.getKey();
-                        if (!dsChanging.containsKey(dsInfo)) {
-                            final RequestedState state = opEntry.getValue();
-                            if (state == RequestedState.WRITE_REQUESTED
-                                    || state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
-                                if (now > writeTimes.get(dsInfo)) {
-                                    try {
-                                        Lock lock = lockManager.lock(dsInfo, LockType.SHARED);
-                                        logger.debug("Will process " + dsInfo + " with " + state);
-                                        writeTimes.remove(dsInfo);
-                                        dsChanging.put(dsInfo, RequestedState.WRITE_REQUESTED);
-                                        it.remove();
-                                        final Thread w = new Thread(
-                                                new DsWriter(dsInfo, propertyHandler, FiniteStateMachine.this, reader, lock));
-                                        w.start();
-                                        if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
-                                            newOps.put(dsInfo, RequestedState.ARCHIVE_REQUESTED);
-                                        }
-                                    } catch (AlreadyLockedException e) {
-                                        logger.debug("Could not acquire lock on " + dsInfo + ", hold back process with " + state);
-                                    } catch (IOException e) {
-                                        logger.error("I/O exception " + e.getMessage() + " locking " + dsInfo);
-                                    }
-                                }
-                            } else if (state == RequestedState.ARCHIVE_REQUESTED) {
-                                try {
-                                    Lock lock = lockManager.lock(dsInfo, LockType.EXCLUSIVE);
-                                    it.remove();
-                                    long dsId = dsInfo.getDsId();
-                                    logger.debug("Will process " + dsInfo + " with " + state);
-                                    dsChanging.put(dsInfo, state);
-                                    final Thread w = new Thread(
-                                            new DsArchiver(dsInfo, propertyHandler, FiniteStateMachine.this, lock));
-                                    w.start();
-                                } catch (AlreadyLockedException e) {
-                                    logger.debug("Could not acquire lock on " + dsInfo + ", hold back process with " + state);
-                                } catch (IOException e) {
-                                    logger.error("I/O exception " + e.getMessage() + " locking " + dsInfo);
-                                }
-                            } else if (state == RequestedState.RESTORE_REQUESTED) {
-                                try {
-                                    Lock lock = lockManager.lock(dsInfo, LockType.EXCLUSIVE);
-                                    logger.debug("Will process " + dsInfo + " with " + state);
-                                    dsChanging.put(dsInfo, state);
-                                    it.remove();
-                                    final Thread w = new Thread(
-                                            new DsRestorer(dsInfo, propertyHandler, FiniteStateMachine.this, reader, lock));
-                                    w.start();
-                                } catch (AlreadyLockedException e) {
-                                    logger.debug("Could not acquire lock on " + dsInfo + ", hold back process with " + state);
-                                } catch (IOException e) {
-                                    logger.error("I/O exception " + e.getMessage() + " locking " + dsInfo);
-                                }
-                            }
-                        }
-                    }
-                    deferredDsOpsQueue.putAll(newOps);
-                }
-
-            } finally {
-                timer.schedule(new DsProcessQueue(), processQueueIntervalMillis);
-            }
-
-        }
-
-    }
-
-    public enum RequestedState {
-        ARCHIVE_REQUESTED, DELETE_REQUESTED, RESTORE_REQUESTED, WRITE_REQUESTED, WRITE_THEN_ARCHIVE_REQUESTED
-    }
-
-    private static Logger logger = LoggerFactory.getLogger(FiniteStateMachine.class);
-
-    /*
-     * Note that the veriable processOpsDelayMillis is used to either delay all deferred
-     * datafile operations or to delay dataset writes, depending on the setting of storageUnit.
-     */
-    private long processOpsDelayMillis;
-
-    private Map<DfInfoImpl, RequestedState> deferredDfOpsQueue = new HashMap<>();
-
-    private Map<DsInfo, RequestedState> deferredDsOpsQueue = new HashMap<>();
-
-    private Map<DfInfo, RequestedState> dfChanging = new HashMap<>();
-
-    private Map<DsInfo, RequestedState> dsChanging = new HashMap<>();
-
-    private Path markerDir;
-    private long processQueueIntervalMillis;
-
-    private PropertyHandler propertyHandler;
-    @EJB
-    IcatReader reader;
-
-    @EJB
-    private LockManager lockManager;
-
-    private StorageUnit storageUnit;
-
-    private Timer timer = new Timer("FSM Timer");
-
-    private Long processOpsTime;
-
-    private Map<DsInfo, Long> writeTimes = new HashMap<>();
-
-    private Set<Long> failures = ConcurrentHashMap.newKeySet();
-
-    @PreDestroy
-    private void exit() {
-        timer.cancel();
-        logger.info("Cancelled timer");
-    }
-
-    /**
-     * Find any DfInfo which may be offline
-     */
-    public Set<DfInfo> getDfMaybeOffline() {
-        Map<DfInfo, RequestedState> union;
-        synchronized (deferredDfOpsQueue) {
-            union = new HashMap<>(dfChanging);
-            union.putAll(deferredDfOpsQueue);
-        }
-        Set<DfInfo> result = new HashSet<>();
-        for (Entry<DfInfo, RequestedState> entry : union.entrySet()) {
-            if (entry.getValue() != RequestedState.WRITE_REQUESTED) {
-                result.add(entry.getKey());
-            }
-        }
-        return result;
-    }
-
-    /**
-     * Find any DfInfo which are being restored or are queued for restoration
-     */
-    public Set<DfInfo> getDfRestoring() {
-        Map<DfInfo, RequestedState> union;
-        synchronized (deferredDfOpsQueue) {
-            union = new HashMap<>(dfChanging);
-            union.putAll(deferredDfOpsQueue);
-        }
-        Set<DfInfo> result = new HashSet<>();
-        for (Entry<DfInfo, RequestedState> entry : union.entrySet()) {
-            if (entry.getValue() == RequestedState.RESTORE_REQUESTED) {
-                result.add(entry.getKey());
-            }
-        }
-        return result;
-    }
-
-    /**
-     * Find any DsInfo which may be offline
-     */
-    public Set<DsInfo> getDsMaybeOffline() {
-        Map<DsInfo, RequestedState> union;
-        synchronized (deferredDsOpsQueue) {
-            union = new HashMap<>(dsChanging);
-            union.putAll(deferredDsOpsQueue);
-        }
-        Set<DsInfo> result = new HashSet<>();
-        for (Entry<DsInfo, RequestedState> entry : union.entrySet()) {
-            if (entry.getValue() != RequestedState.WRITE_REQUESTED) {
-                result.add(entry.getKey());
-            }
-        }
-        return result;
-    }
-
-    /**
-     * Find any DsInfo which are being restored or are queued for restoration
-     */
-    public Set<DsInfo> getDsRestoring() {
-        Map<DsInfo, RequestedState> union;
-        synchronized (deferredDsOpsQueue) {
-            union = new HashMap<>(dsChanging);
-            union.putAll(deferredDsOpsQueue);
-        }
-        Set<DsInfo> result = new HashSet<>();
-        for (Entry<DsInfo, RequestedState> entry : union.entrySet()) {
-            if (entry.getValue() == RequestedState.RESTORE_REQUESTED) {
-                result.add(entry.getKey());
-            }
-        }
-        return result;
-    }
-
-    public String getServiceStatus() throws InternalException {
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-            if (storageUnit == null) {
-                gen.writeStartArray("opsQueue").writeEnd();
-            } else if (storageUnit == StorageUnit.DATASET) {
-                Map<DsInfo, RequestedState> union;
-                synchronized (deferredDsOpsQueue) {
-                    union = new HashMap<>(dsChanging);
-                    union.putAll(deferredDsOpsQueue);
-                }
-                gen.writeStartArray("opsQueue");
-                for (Entry<DsInfo, RequestedState> entry : union.entrySet()) {
-                    DsInfo item = entry.getKey();
-                    gen.writeStartObject().write("data", item.toString()).write("request", entry.getValue().name())
-                            .writeEnd();
-                }
-                gen.writeEnd(); // end Array("opsQueue")
-            } else if (storageUnit == StorageUnit.DATAFILE) {
-                Map<DfInfo, RequestedState> union;
-                synchronized (deferredDfOpsQueue) {
-                    union = new HashMap<>(dfChanging);
-                    union.putAll(deferredDfOpsQueue);
-                }
-                gen.writeStartArray("opsQueue");
-                for (Entry<DfInfo, RequestedState> entry : union.entrySet()) {
-                    DfInfo item = entry.getKey();
-                    gen.writeStartObject().write("data", item.toString()).write("request", entry.getValue().name())
-                            .writeEnd();
-                }
-                gen.writeEnd(); // end Array("opsQueue")
-            }
-
-            Collection<LockInfo> lockInfo = lockManager.getLockInfo();
-            gen.write("lockCount", lockInfo.size());
-            gen.writeStartArray("locks");
-            for (LockInfo li : lockInfo) {
-                gen.writeStartObject().write("id", li.id).write("type", li.type.name()).write("count", li.count).writeEnd();
-            }
-            gen.writeEnd(); // end Array("locks")
-
-            gen.writeStartArray("failures");
-            for (Long failure : failures) {
-                gen.write(failure);
-            }
-            gen.writeEnd(); // end Array("failures")
-
-            gen.writeEnd(); // end Object()
-        }
-        return baos.toString();
-    }
-
-    @PostConstruct
-    private void init() {
-        try {
-            propertyHandler = PropertyHandler.getInstance();
-            processQueueIntervalMillis = propertyHandler.getProcessQueueIntervalSeconds() * 1000L;
-            storageUnit = propertyHandler.getStorageUnit();
-            if (storageUnit == StorageUnit.DATASET) {
-                processOpsDelayMillis = propertyHandler.getDelayDatasetWrites() * 1000L;
-                timer.schedule(new DsProcessQueue(), processQueueIntervalMillis);
-                logger.info("DsProcessQueue scheduled to run in " + processQueueIntervalMillis + " milliseconds");
-            } else if (storageUnit == StorageUnit.DATAFILE) {
-                processOpsDelayMillis = propertyHandler.getDelayDatafileOperations() * 1000L;
-                timer.schedule(new DfProcessQueue(), processQueueIntervalMillis);
-                logger.info("DfProcessQueue scheduled to run in " + processQueueIntervalMillis + " milliseconds");
-            }
-            markerDir = propertyHandler.getCacheDir().resolve("marker");
-            Files.createDirectories(markerDir);
-        } catch (IOException e) {
-            throw new RuntimeException("FiniteStateMachine reports " + e.getClass() + " " + e.getMessage());
-        }
-    }
-
-    public void queue(DfInfoImpl dfInfo, DeferredOp deferredOp) throws InternalException {
-        logger.info("Requesting " + deferredOp + " of datafile " + dfInfo);
-
-        synchronized (deferredDfOpsQueue) {
-
-            if (processOpsTime == null) {
-                processOpsTime = System.currentTimeMillis() + processOpsDelayMillis;
-                final Date d = new Date(processOpsTime);
-                logger.debug("Requesting delay operations till " + d);
-            }
-
-            final RequestedState state = this.deferredDfOpsQueue.get(dfInfo);
-            if (state == null) {
-                if (deferredOp == DeferredOp.WRITE) {
-                    try {
-                        Path marker = markerDir.resolve(Long.toString(dfInfo.getDfId()));
-                        Files.createFile(marker);
-                        logger.debug("Created marker " + marker);
-                    } catch (FileAlreadyExistsException e) {
-                        // Pass will ignore this
-                    } catch (IOException e) {
-                        throw new InternalException(e.getClass() + " " + e.getMessage());
-                    }
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.WRITE_REQUESTED);
-                } else if (deferredOp == DeferredOp.ARCHIVE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.ARCHIVE_REQUESTED);
-                } else if (deferredOp == DeferredOp.RESTORE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.RESTORE_REQUESTED);
-                } else if (deferredOp == DeferredOp.DELETE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.DELETE_REQUESTED);
-                }
-            } else if (state == RequestedState.ARCHIVE_REQUESTED) {
-                if (deferredOp == DeferredOp.RESTORE) {
-                    deferredDfOpsQueue.remove(dfInfo);
-                } else if (deferredOp == DeferredOp.DELETE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.DELETE_REQUESTED);
-                }
-            } else if (state == RequestedState.DELETE_REQUESTED) {
-                // No way out
-            } else if (state == RequestedState.RESTORE_REQUESTED) {
-                if (deferredOp == DeferredOp.DELETE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.DELETE_REQUESTED);
-                } else if (deferredOp == DeferredOp.ARCHIVE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.ARCHIVE_REQUESTED);
-                }
-            } else if (state == RequestedState.WRITE_REQUESTED) {
-                if (deferredOp == DeferredOp.DELETE) {
-                    deferredDfOpsQueue.remove(dfInfo);
-                } else if (deferredOp == DeferredOp.ARCHIVE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.WRITE_THEN_ARCHIVE_REQUESTED);
-                }
-            } else if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
-                if (deferredOp == DeferredOp.DELETE) {
-                    deferredDfOpsQueue.remove(dfInfo);
-                } else if (deferredOp == DeferredOp.RESTORE) {
-                    deferredDfOpsQueue.put(dfInfo, RequestedState.WRITE_REQUESTED);
-                }
-            }
-        }
-    }
-
-    public void queue(DsInfo dsInfo, DeferredOp deferredOp) throws InternalException {
-        logger.info("Requesting " + deferredOp + " of dataset " + dsInfo);
-
-        synchronized (deferredDsOpsQueue) {
-
-            final RequestedState state = this.deferredDsOpsQueue.get(dsInfo);
-            if (state == null) {
-                if (deferredOp == DeferredOp.WRITE) {
-                    requestWrite(dsInfo);
-                } else if (deferredOp == DeferredOp.ARCHIVE) {
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.ARCHIVE_REQUESTED);
-                } else if (deferredOp == DeferredOp.RESTORE) {
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.RESTORE_REQUESTED);
-                }
-            } else if (state == RequestedState.ARCHIVE_REQUESTED) {
-                if (deferredOp == DeferredOp.WRITE) {
-                    requestWrite(dsInfo);
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.WRITE_THEN_ARCHIVE_REQUESTED);
-                } else if (deferredOp == DeferredOp.RESTORE) {
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.RESTORE_REQUESTED);
-                }
-            } else if (state == RequestedState.RESTORE_REQUESTED) {
-                if (deferredOp == DeferredOp.WRITE) {
-                    requestWrite(dsInfo);
-                } else if (deferredOp == DeferredOp.ARCHIVE) {
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.ARCHIVE_REQUESTED);
-                }
-            } else if (state == RequestedState.WRITE_REQUESTED) {
-                if (deferredOp == DeferredOp.WRITE) {
-                    setDelay(dsInfo);
-                } else if (deferredOp == DeferredOp.ARCHIVE) {
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.WRITE_THEN_ARCHIVE_REQUESTED);
-                }
-            } else if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
-                if (deferredOp == DeferredOp.WRITE) {
-                    setDelay(dsInfo);
-                } else if (deferredOp == DeferredOp.RESTORE) {
-                    deferredDsOpsQueue.put(dsInfo, RequestedState.WRITE_REQUESTED);
-                }
-            }
-        }
-
-    }
-
-    public void removeFromChanging(DfInfo dfInfo) {
-        synchronized (deferredDfOpsQueue) {
-            dfChanging.remove(dfInfo);
-        }
-    }
-
-    public void removeFromChanging(DsInfo dsInfo) {
-        synchronized (deferredDsOpsQueue) {
-            dsChanging.remove(dsInfo);
-        }
-    }
-
-    private void requestWrite(DsInfo dsInfo) throws InternalException {
-        try {
-            Path marker = markerDir.resolve(Long.toString(dsInfo.getDsId()));
-            Files.createFile(marker);
-            logger.debug("Created marker " + marker);
-        } catch (FileAlreadyExistsException e) {
-            // Pass will ignore this
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-        deferredDsOpsQueue.put(dsInfo, RequestedState.WRITE_REQUESTED);
-        setDelay(dsInfo);
-    }
-
-    private void setDelay(DsInfo dsInfo) {
-        writeTimes.put(dsInfo, System.currentTimeMillis() + processOpsDelayMillis);
-        if (logger.isDebugEnabled()) {
-            final Date d = new Date(writeTimes.get(dsInfo));
-            logger.debug("Requesting delay of writing of dataset " + dsInfo + " till " + d);
-        }
-    }
-
-    public void recordSuccess(Long id) {
-        if (failures.remove(id)) {
-            logger.debug("Marking {} OK", id);
-        }
-    }
-
-    public void recordFailure(Long id) {
-        if (failures.add(id)) {
-            logger.debug("Marking {} as failure", id);
-        }
-    }
-
-    public void checkFailure(Long id) throws InternalException {
-        if (failures.contains(id)) {
-            throw new InternalException("Restore failed");
-        }
-    }
-
-}
diff --git a/src/main/java/org/icatproject/ids/IdsBean.java b/src/main/java/org/icatproject/ids/IdsBean.java
deleted file mode 100644
index a6cf2c25..00000000
--- a/src/main/java/org/icatproject/ids/IdsBean.java
+++ /dev/null
@@ -1,2215 +0,0 @@
-package org.icatproject.ids;
-
-import java.io.BufferedOutputStream;
-import java.io.ByteArrayOutputStream;
-import java.io.File;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.net.HttpURLConnection;
-import java.nio.file.Files;
-import java.nio.file.NoSuchFileException;
-import java.nio.file.Path;
-import java.security.NoSuchAlgorithmException;
-import java.text.SimpleDateFormat;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Date;
-import java.util.GregorianCalendar;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.OptionalLong;
-import java.util.Set;
-import java.util.SortedMap;
-import java.util.SortedSet;
-import java.util.TreeMap;
-import java.util.TreeSet;
-import java.util.UUID;
-import java.util.concurrent.Callable;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.Future;
-import java.util.concurrent.atomic.AtomicLong;
-import java.util.concurrent.locks.ReentrantLock;
-import java.util.regex.Pattern;
-import java.util.zip.CRC32;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipException;
-import java.util.zip.ZipOutputStream;
-import javax.xml.datatype.DatatypeFactory;
-
-import jakarta.annotation.PostConstruct;
-import jakarta.ejb.EJB;
-import jakarta.ejb.Stateless;
-import jakarta.json.Json;
-import jakarta.json.JsonNumber;
-import jakarta.json.JsonObject;
-import jakarta.json.JsonReader;
-import jakarta.json.JsonValue;
-import jakarta.json.stream.JsonGenerator;
-import static jakarta.ws.rs.core.HttpHeaders.CONTENT_LENGTH;
-import jakarta.ws.rs.core.Response;
-import jakarta.ws.rs.core.StreamingOutput;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import org.icatproject.Datafile;
-import org.icatproject.DatafileFormat;
-import org.icatproject.Dataset;
-import org.icatproject.EntityBaseBean;
-import org.icatproject.ICAT;
-import org.icatproject.IcatExceptionType;
-import org.icatproject.IcatException_Exception;
-import org.icatproject.ids.DataSelection.Returns;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.LockManager.LockType;
-import org.icatproject.ids.exceptions.BadRequestException;
-import org.icatproject.ids.exceptions.DataNotOnlineException;
-import org.icatproject.ids.exceptions.IdsException;
-import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
-import org.icatproject.ids.exceptions.InternalException;
-import org.icatproject.ids.exceptions.NotFoundException;
-import org.icatproject.ids.exceptions.NotImplementedException;
-import org.icatproject.ids.plugin.AlreadyLockedException;
-import org.icatproject.ids.plugin.ArchiveStorageInterface;
-import org.icatproject.ids.plugin.DfInfo;
-import org.icatproject.ids.plugin.DsInfo;
-import org.icatproject.ids.plugin.MainStorageInterface;
-import org.icatproject.ids.plugin.ZipMapperInterface;
-import org.icatproject.utils.IcatSecurity;
-import org.icatproject.utils.ShellCommand;
-
-@Stateless
-public class IdsBean {
-
-    public class RunPrepDsCheck implements Callable<Void> {
-
-        private Collection<DsInfo> toCheck;
-        private Set<Long> emptyDatasets;
-
-        public RunPrepDsCheck(Collection<DsInfo> toCheck, Set<Long> emptyDatasets) {
-            this.toCheck = toCheck;
-            this.emptyDatasets = emptyDatasets;
-        }
-
-        @Override
-        public Void call() throws Exception {
-            for (DsInfo dsInfo : toCheck) {
-                fsm.checkFailure(dsInfo.getDsId());
-                restoreIfOffline(dsInfo, emptyDatasets);
-            }
-            return null;
-        }
-
-    }
-
-    public class RunPrepDfCheck implements Callable<Void> {
-
-        private SortedSet<DfInfoImpl> toCheck;
-
-        public RunPrepDfCheck(SortedSet<DfInfoImpl> toCheck) {
-            this.toCheck = toCheck;
-        }
-
-        @Override
-        public Void call() throws Exception {
-            for (DfInfoImpl dfInfo : toCheck) {
-                fsm.checkFailure(dfInfo.getDfId());
-                restoreIfOffline(dfInfo);
-            }
-            return null;
-        }
-
-    }
-
-    enum CallType {
-        INFO, PREPARE, READ, WRITE, MIGRATE
-    }
-
-    public class RestoreDfTask implements Callable<Void> {
-
-        private Set<DfInfoImpl> dfInfos;
-
-        public RestoreDfTask(Set<DfInfoImpl> dfInfos) {
-            this.dfInfos = dfInfos;
-        }
-
-        @Override
-        public Void call() throws Exception {
-            for (DfInfoImpl dfInfo : dfInfos) {
-                restoreIfOffline(dfInfo);
-            }
-            return null;
-        }
-
-    }
-
-    public class RestoreDsTask implements Callable<Void> {
-        private Collection<DsInfo> dsInfos;
-        private Set<Long> emptyDs;
-
-        public RestoreDsTask(Collection<DsInfo> dsInfos, Set<Long> emptyDs) {
-            this.dsInfos = dsInfos;
-            this.emptyDs = emptyDs;
-        }
-
-        @Override
-        public Void call() throws Exception {
-            for (DsInfo dsInfo : dsInfos) {
-                restoreIfOffline(dsInfo, emptyDs);
-            }
-            return null;
-        }
-    }
-
-    private class SO implements StreamingOutput {
-
-        private long offset;
-        private boolean zip;
-        private Map<Long, DsInfo> dsInfos;
-        private Lock lock;
-        private boolean compress;
-        private Set<DfInfoImpl> dfInfos;
-        private String ip;
-        private long start;
-        private Long transferId;
-
-        SO(Map<Long, DsInfo> dsInfos, Set<DfInfoImpl> dfInfos, long offset, boolean zip, boolean compress,
-           Lock lock, Long transferId, String ip, long start) {
-            this.offset = offset;
-            this.zip = zip;
-            this.dsInfos = dsInfos;
-            this.dfInfos = dfInfos;
-            this.lock = lock;
-            this.compress = compress;
-            this.transferId = transferId;
-            this.ip = ip;
-            this.start = start;
-        }
-
-        @Override
-        public void write(OutputStream output) throws IOException {
-            Object transfer = "??";
-            try {
-                if (offset != 0) { // Wrap the stream if needed
-                    output = new RangeOutputStream(output, offset, null);
-                }
-                byte[] bytes = new byte[BUFSIZ];
-                if (zip) {
-                    ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(output));
-                    if (!compress) {
-                        zos.setLevel(0); // Otherwise use default compression
-                    }
-
-                    for (DfInfoImpl dfInfo : dfInfos) {
-                        logger.debug("Adding " + dfInfo + " to zip");
-                        transfer = dfInfo;
-                        DsInfo dsInfo = dsInfos.get(dfInfo.getDsId());
-                        String entryName = zipMapper.getFullEntryName(dsInfo, dfInfo);
-                        InputStream stream = null;
-                        try {
-                            zos.putNextEntry(new ZipEntry(entryName));
-                            stream = mainStorage.get(dfInfo.getDfLocation(), dfInfo.getCreateId(), dfInfo.getModId());
-                            int length;
-                            while ((length = stream.read(bytes)) >= 0) {
-                                zos.write(bytes, 0, length);
-                            }
-                        } catch (ZipException e) {
-                            logger.debug("Skipped duplicate");
-                        }
-                        zos.closeEntry();
-                        if (stream != null) {
-                            stream.close();
-                        }
-                    }
-                    zos.close();
-                } else {
-                    DfInfoImpl dfInfo = dfInfos.iterator().next();
-                    transfer = dfInfo;
-                    InputStream stream = mainStorage.get(dfInfo.getDfLocation(), dfInfo.getCreateId(),
-                            dfInfo.getModId());
-                    int length;
-                    while ((length = stream.read(bytes)) >= 0) {
-                        output.write(bytes, 0, length);
-                    }
-                    output.close();
-                    stream.close();
-                }
-
-                if (transferId != null) {
-                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                    try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                        gen.write("transferId", transferId);
-                        gen.writeEnd();
-                    }
-                    transmitter.processMessage("getData", ip, baos.toString(), start);
-                }
-
-            } catch (IOException e) {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("transferId", transferId);
-                    gen.write("exceptionClass", e.getClass().toString());
-                    gen.write("exceptionMessage", e.getMessage());
-                    gen.writeEnd();
-                }
-                transmitter.processMessage("getData", ip, baos.toString(), start);
-                logger.error("Failed to stream " + transfer + " due to " + e.getMessage());
-                throw e;
-            } finally {
-                lock.release();
-            }
-        }
-
-    }
-
-    private static final int BUFSIZ = 2048;
-
-    private static Boolean inited = false;
-
-    private static String key;
-
-    private final static Logger logger = LoggerFactory.getLogger(IdsBean.class);
-    private static String paddedPrefix;
-    private static final String prefix = "<html><script type=\"text/javascript\">window.name='";
-    private static final String suffix = "';</script></html>";
-
-    /**
-     * matches standard UUID format of 8-4-4-4-12 hexadecimal digits
-     */
-    public static final Pattern uuidRegExp = Pattern
-            .compile("^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$");
-
-    static {
-        paddedPrefix = "<html><script type=\"text/javascript\">/*";
-        for (int n = 1; n < 25; n++) {
-            paddedPrefix += " *        \n";
-        }
-        paddedPrefix += "*/window.name='";
-    }
-
-    static void cleanDatasetCache(Path datasetDir) {
-        for (File dsFile : datasetDir.toFile().listFiles()) {
-            Path path = dsFile.toPath();
-            try {
-                long thisSize = Files.size(path);
-                Files.delete(path);
-                logger.debug("Deleted " + path + " to reclaim " + thisSize + " bytes");
-            } catch (IOException e) {
-                logger.debug("Failed to delete " + path + " " + e.getClass() + " " + e.getMessage());
-            }
-        }
-    }
-
-    static void cleanPreparedDir(Path preparedDir) {
-        for (File file : preparedDir.toFile().listFiles()) {
-            Path path = file.toPath();
-            String pf = path.getFileName().toString();
-            if (pf.startsWith("tmp.") || pf.endsWith(".tmp")) {
-                try {
-                    long thisSize = 0;
-                    if (Files.isDirectory(path)) {
-                        for (File notZipFile : file.listFiles()) {
-                            thisSize += Files.size(notZipFile.toPath());
-                            Files.delete(notZipFile.toPath());
-                        }
-                    }
-                    thisSize += Files.size(path);
-                    Files.delete(path);
-                    logger.debug("Deleted " + path + " to reclaim " + thisSize + " bytes");
-                } catch (IOException e) {
-                    logger.debug("Failed to delete " + path + e.getMessage());
-                }
-            }
-        }
-    }
-
-    public static String getLocation(long dfid, String location)
-            throws InsufficientPrivilegesException, InternalException {
-        if (location == null) {
-            throw new InternalException("location is null");
-        }
-        if (key == null) {
-            return location;
-        } else {
-            return getLocationFromDigest(dfid, location, key);
-        }
-    }
-
-    static String getLocationFromDigest(long id, String locationWithHash, String key)
-            throws InternalException, InsufficientPrivilegesException {
-        int i = locationWithHash.lastIndexOf(' ');
-        try {
-            String location = locationWithHash.substring(0, i);
-            String hash = locationWithHash.substring(i + 1);
-            if (!hash.equals(IcatSecurity.digest(id, location, key))) {
-                throw new InsufficientPrivilegesException(
-                        "Location \"" + locationWithHash + "\" does not contain a valid hash.");
-            }
-            return location;
-        } catch (IndexOutOfBoundsException e) {
-            throw new InsufficientPrivilegesException("Location \"" + locationWithHash + "\" does not contain hash.");
-        } catch (NoSuchAlgorithmException e) {
-            throw new InternalException(e.getMessage());
-        }
-    }
-
-    static void pack(OutputStream stream, boolean zip, boolean compress, Map<Long, DsInfo> dsInfos,
-                     Set<DfInfoImpl> dfInfos, Set<Long> emptyDatasets) {
-        JsonGenerator gen = Json.createGenerator(stream);
-        gen.writeStartObject();
-        gen.write("zip", zip);
-        gen.write("compress", compress);
-
-        gen.writeStartArray("dsInfo");
-        for (DsInfo dsInfo : dsInfos.values()) {
-            logger.debug("dsInfo " + dsInfo);
-            gen.writeStartObject().write("dsId", dsInfo.getDsId())
-
-                    .write("dsName", dsInfo.getDsName()).write("facilityId", dsInfo.getFacilityId())
-                    .write("facilityName", dsInfo.getFacilityName()).write("invId", dsInfo.getInvId())
-                    .write("invName", dsInfo.getInvName()).write("visitId", dsInfo.getVisitId());
-            if (dsInfo.getDsLocation() != null) {
-                gen.write("dsLocation", dsInfo.getDsLocation());
-            } else {
-                gen.writeNull("dsLocation");
-            }
-            gen.writeEnd();
-        }
-        gen.writeEnd();
-
-        gen.writeStartArray("dfInfo");
-        for (DfInfoImpl dfInfo : dfInfos) {
-            DsInfo dsInfo = dsInfos.get(dfInfo.getDsId());
-            gen.writeStartObject().write("dsId", dsInfo.getDsId()).write("dfId", dfInfo.getDfId())
-                    .write("dfName", dfInfo.getDfName()).write("createId", dfInfo.getCreateId())
-                    .write("modId", dfInfo.getModId());
-            if (dfInfo.getDfLocation() != null) {
-                gen.write("dfLocation", dfInfo.getDfLocation());
-            } else {
-                gen.writeNull("dfLocation");
-            }
-            gen.writeEnd();
-
-        }
-        gen.writeEnd();
-
-        gen.writeStartArray("emptyDs");
-        for (Long emptyDs : emptyDatasets) {
-            gen.write(emptyDs);
-        }
-        gen.writeEnd();
-
-        gen.writeEnd().close();
-
-    }
-
-    static Prepared unpack(InputStream stream) throws InternalException {
-        Prepared prepared = new Prepared();
-        JsonObject pd;
-        try (JsonReader jsonReader = Json.createReader(stream)) {
-            pd = jsonReader.readObject();
-        }
-        prepared.zip = pd.getBoolean("zip");
-        prepared.compress = pd.getBoolean("compress");
-        SortedMap<Long, DsInfo> dsInfos = new TreeMap<>();
-        SortedSet<DfInfoImpl> dfInfos = new TreeSet<>();
-        Set<Long> emptyDatasets = new HashSet<>();
-
-        for (JsonValue itemV : pd.getJsonArray("dfInfo")) {
-            JsonObject item = (JsonObject) itemV;
-            String dfLocation = item.isNull("dfLocation") ? null : item.getString("dfLocation");
-            dfInfos.add(new DfInfoImpl(item.getJsonNumber("dfId").longValueExact(), item.getString("dfName"),
-                    dfLocation, item.getString("createId"), item.getString("modId"),
-                    item.getJsonNumber("dsId").longValueExact()));
-
-        }
-        prepared.dfInfos = dfInfos;
-
-        for (JsonValue itemV : pd.getJsonArray("dsInfo")) {
-            JsonObject item = (JsonObject) itemV;
-            long dsId = item.getJsonNumber("dsId").longValueExact();
-            String dsLocation = item.isNull("dsLocation") ? null : item.getString("dsLocation");
-            dsInfos.put(dsId, new DsInfoImpl(dsId, item.getString("dsName"), dsLocation,
-                    item.getJsonNumber("invId").longValueExact(), item.getString("invName"), item.getString("visitId"),
-                    item.getJsonNumber("facilityId").longValueExact(), item.getString("facilityName")));
-        }
-        prepared.dsInfos = dsInfos;
-
-        for (JsonValue itemV : pd.getJsonArray("emptyDs")) {
-            emptyDatasets.add(((JsonNumber) itemV).longValueExact());
-        }
-        prepared.emptyDatasets = emptyDatasets;
-
-        return prepared;
-    }
-
-    public static void validateUUID(String thing, String id) throws BadRequestException {
-        if (id == null || !uuidRegExp.matcher(id).matches())
-            throw new BadRequestException("The " + thing + " parameter '" + id + "' is not a valid UUID");
-    }
-
-    private static AtomicLong atomicLong = new AtomicLong();
-
-    @EJB
-    Transmitter transmitter;
-
-    private ExecutorService threadPool;
-
-    private ArchiveStorageInterface archiveStorage;
-
-    private Path datasetDir;
-
-    private DatatypeFactory datatypeFactory;
-
-    private boolean enableWrite;
-
-    @EJB
-    private FiniteStateMachine fsm;
-
-    @EJB
-    private LockManager lockManager;
-
-    private ICAT icat;
-
-    private MainStorageInterface mainStorage;
-
-    private Path markerDir;
-
-    private Path preparedDir;
-
-    private PropertyHandler propertyHandler;
-
-    @EJB
-    IcatReader reader;
-
-    private boolean readOnly;
-
-    private Set<String> rootUserNames;
-
-    private StorageUnit storageUnit;
-
-    private ZipMapperInterface zipMapper;
-
-    private int maxIdsInQuery;
-
-    private boolean twoLevel;
-
-    private Set<CallType> logSet;
-
-    class PreparedStatus {
-        public ReentrantLock lock = new ReentrantLock();
-        public DfInfoImpl fromDfElement;
-        public Future<?> future;
-        public Long fromDsElement;
-    }
-
-    private Map<String, PreparedStatus> preparedStatusMap = new ConcurrentHashMap<>();
-
-    private void addIds(JsonGenerator gen, String investigationIds, String datasetIds, String datafileIds)
-            throws BadRequestException {
-        if (investigationIds != null) {
-            gen.writeStartArray("investigationIds");
-            for (long invid : DataSelection.getValidIds("investigationIds", investigationIds)) {
-                gen.write(invid);
-            }
-            gen.writeEnd();
-        }
-        if (datasetIds != null) {
-            gen.writeStartArray("datasetIds");
-            for (long invid : DataSelection.getValidIds("datasetIds", datasetIds)) {
-                gen.write(invid);
-            }
-            gen.writeEnd();
-        }
-        if (datafileIds != null) {
-            gen.writeStartArray("datafileIds");
-            for (long invid : DataSelection.getValidIds("datafileIds", datafileIds)) {
-                gen.write(invid);
-            }
-            gen.writeEnd();
-        }
-    }
-
-    public void archive(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
-            NotFoundException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: archive " + "investigationIds='" + investigationIds + "' " + "datasetIds='"
-                + datasetIds + "' " + "datafileIds='" + datafileIds + "'");
-
-        validateUUID("sessionId", sessionId);
-
-        // Do it
-        if (storageUnit == StorageUnit.DATASET) {
-            DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATASETS);
-            Map<Long, DsInfo> dsInfos = dataSelection.getDsInfo();
-            for (DsInfo dsInfo : dsInfos.values()) {
-                fsm.queue(dsInfo, DeferredOp.ARCHIVE);
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATAFILES);
-            Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-            for (DfInfoImpl dfInfo : dfInfos) {
-                fsm.queue(dfInfo, DeferredOp.ARCHIVE);
-            }
-        } else {
-            throw new NotImplementedException("This operation is unavailable for single level storage");
-        }
-
-        if (logSet.contains(CallType.MIGRATE)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("archive", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-    }
-
-    private void checkDatafilesPresent(Set<? extends DfInfo> dfInfos)
-            throws NotFoundException, InternalException {
-        /* Check that datafiles have not been deleted before locking */
-        int n = 0;
-        StringBuffer sb = new StringBuffer("SELECT COUNT(df) from Datafile df WHERE (df.id in (");
-        for (DfInfo dfInfo : dfInfos) {
-            if (n != 0) {
-                sb.append(',');
-            }
-            sb.append(dfInfo.getDfId());
-            if (++n == maxIdsInQuery) {
-                try {
-                    if (((Long) reader.search(sb.append("))").toString()).get(0)).intValue() != n) {
-                        throw new NotFoundException("One of the data files requested has been deleted");
-                    }
-                    n = 0;
-                    sb = new StringBuffer("SELECT COUNT(df) from Datafile df WHERE (df.id in (");
-                } catch (IcatException_Exception e) {
-                    throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
-                }
-            }
-        }
-        if (n != 0) {
-            try {
-                if (((Long) reader.search(sb.append("))").toString()).get(0)).intValue() != n) {
-                    throw new NotFoundException("One of the datafiles requested has been deleted");
-                }
-            } catch (IcatException_Exception e) {
-                throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
-            }
-        }
-
-    }
-
-    private void checkOnline(Collection<DsInfo> dsInfos, Set<Long> emptyDatasets,
-                             Set<DfInfoImpl> dfInfos)
-            throws InternalException, DataNotOnlineException {
-        if (storageUnit == StorageUnit.DATASET) {
-            boolean maybeOffline = false;
-            for (DsInfo dsInfo : dsInfos) {
-                if (restoreIfOffline(dsInfo, emptyDatasets)) {
-                    maybeOffline = true;
-                }
-            }
-            if (maybeOffline) {
-                throw new DataNotOnlineException(
-                        "Before putting, getting or deleting a datafile, its dataset has to be restored, restoration requested automatically");
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            boolean maybeOffline = false;
-            for (DfInfoImpl dfInfo : dfInfos) {
-                if (restoreIfOffline(dfInfo)) {
-                    maybeOffline = true;
-                }
-            }
-            if (maybeOffline) {
-                throw new DataNotOnlineException(
-                        "Before getting a datafile, it must be restored, restoration requested automatically");
-            }
-        }
-    }
-
-    public void delete(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
-            NotFoundException, DataNotOnlineException {
-
-        long start = System.currentTimeMillis();
-
-        logger.info("New webservice request: delete " + "investigationIds='" + investigationIds + "' " + "datasetIds='"
-                + datasetIds + "' " + "datafileIds='" + datafileIds + "'");
-
-        if (readOnly) {
-            throw new NotImplementedException("This operation has been configured to be unavailable");
-        }
-
-        IdsBean.validateUUID("sessionId", sessionId);
-
-        DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                investigationIds, datasetIds, datafileIds, Returns.DATASETS_AND_DATAFILES);
-
-        // Do it
-        Collection<DsInfo> dsInfos = dataSelection.getDsInfo().values();
-        Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-
-        try (Lock lock = lockManager.lock(dsInfos, LockType.EXCLUSIVE)) {
-            if (storageUnit == StorageUnit.DATASET) {
-                checkOnline(dsInfos, dataSelection.getEmptyDatasets(), dfInfos);
-            }
-
-            /* Now delete from ICAT */
-            List<EntityBaseBean> dfs = new ArrayList<>();
-            for (DfInfoImpl dfInfo : dataSelection.getDfInfo()) {
-                Datafile df = new Datafile();
-                df.setId(dfInfo.getDfId());
-                dfs.add(df);
-            }
-            try {
-                icat.deleteMany(sessionId, dfs);
-            } catch (IcatException_Exception e) {
-                IcatExceptionType type = e.getFaultInfo().getType();
-
-                if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
-                    throw new InsufficientPrivilegesException(e.getMessage());
-                }
-                if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
-                    throw new NotFoundException(e.getMessage());
-                }
-                throw new InternalException(type + " " + e.getMessage());
-            }
-
-            /*
-             * Delete the local copy directly rather than queueing it as it has
-             * been removed from ICAT so will not be accessible to any
-             * subsequent IDS calls.
-             */
-            for (DfInfoImpl dfInfo : dataSelection.getDfInfo()) {
-                String location = dfInfo.getDfLocation();
-                try {
-                    if ((long) reader
-                            .search("SELECT COUNT(df) FROM Datafile df WHERE df.location LIKE '" + location.replaceAll("'", "''") + "%'")
-                            .get(0) == 0) {
-                        if (mainStorage.exists(location)) {
-                            logger.debug("Delete physical file " + location + " from main storage");
-                            mainStorage.delete(location, dfInfo.getCreateId(), dfInfo.getModId());
-                        }
-                        if (storageUnit == StorageUnit.DATAFILE) {
-                            fsm.queue(dfInfo, DeferredOp.DELETE);
-                        }
-                    }
-                } catch (IcatException_Exception e) {
-                    throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
-                } catch (IOException e) {
-                    logger.error("I/O error " + e.getMessage() + " deleting " + dfInfo);
-                    throw new InternalException(e.getClass() + " " + e.getMessage());
-                }
-            }
-
-            if (storageUnit == StorageUnit.DATASET) {
-                for (DsInfo dsInfo : dsInfos) {
-                    fsm.queue(dsInfo, DeferredOp.WRITE);
-                }
-            }
-
-        } catch (AlreadyLockedException e) {
-            logger.debug("Could not acquire lock, delete failed");
-            throw new DataNotOnlineException("Data is busy");
-        } catch (IOException e) {
-            logger.error("I/O error " + e.getMessage());
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        if (logSet.contains(CallType.WRITE)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("delete", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-    }
-
-    public Response getData(String preparedId, String outname, final long offset, String ip) throws BadRequestException,
-            NotFoundException, InternalException, InsufficientPrivilegesException, DataNotOnlineException {
-
-        long time = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: getData preparedId = '" + preparedId + "' outname = '" + outname
-                + "' offset = " + offset);
-
-        validateUUID("preparedId", preparedId);
-
-        // Do it
-        Prepared prepared;
-        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
-            prepared = unpack(stream);
-        } catch (NoSuchFileException e) {
-            throw new NotFoundException("The preparedId " + preparedId + " is not known");
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        final boolean zip = prepared.zip;
-        final boolean compress = prepared.compress;
-        final Set<DfInfoImpl> dfInfos = prepared.dfInfos;
-        final Map<Long, DsInfo> dsInfos = prepared.dsInfos;
-        Set<Long> emptyDatasets = prepared.emptyDatasets;
-
-        Lock lock = null;
-        try {
-            lock = lockManager.lock(dsInfos.values(), LockType.SHARED);
-
-            if (twoLevel) {
-                checkOnline(dsInfos.values(), emptyDatasets, dfInfos);
-            }
-            checkDatafilesPresent(dfInfos);
-
-            /* Construct the name to include in the headers */
-            String name;
-            if (outname == null) {
-                if (zip) {
-                    name = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss").format(new Date()) + ".zip";
-                } else {
-                    name = dfInfos.iterator().next().getDfName();
-                }
-            } else {
-                if (zip) {
-                    String ext = outname.substring(outname.lastIndexOf(".") + 1, outname.length());
-                    if ("zip".equals(ext)) {
-                        name = outname;
-                    } else {
-                        name = outname + ".zip";
-                    }
-                } else {
-                    name = outname;
-                }
-            }
-
-            Long transferId = null;
-            if (logSet.contains(CallType.READ)) {
-                transferId = atomicLong.getAndIncrement();
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("transferId", transferId);
-                    gen.write("preparedId", preparedId);
-                    gen.writeEnd();
-                }
-                transmitter.processMessage("getDataStart", ip, baos.toString(), time);
-            }
-
-            return Response.status(offset == 0 ? HttpURLConnection.HTTP_OK : HttpURLConnection.HTTP_PARTIAL)
-                    .entity(new SO(dsInfos, dfInfos, offset, zip, compress, lock, transferId, ip, time))
-                    .header("Content-Disposition", "attachment; filename=\"" + name + "\"").header("Accept-Ranges", "bytes")
-                    .build();
-        } catch (AlreadyLockedException e) {
-            logger.debug("Could not acquire lock, getData failed");
-            throw new DataNotOnlineException("Data is busy");
-        } catch (IOException e) {
-            if (lock != null) {
-                lock.release();
-            }
-            logger.error("I/O error " + e.getMessage());
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        } catch (IdsException e) {
-            lock.release();
-            throw e;
-        }
-    }
-
-    public Response getData(String sessionId, String investigationIds, String datasetIds, String datafileIds,
-                            final boolean compress, boolean zip, String outname, final long offset, String ip)
-            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
-            DataNotOnlineException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info(String.format("New webservice request: getData investigationIds=%s, datasetIds=%s, datafileIds=%s",
-                investigationIds, datasetIds, datafileIds));
-
-        validateUUID("sessionId", sessionId);
-
-        final DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                investigationIds, datasetIds, datafileIds, Returns.DATASETS_AND_DATAFILES);
-
-        // Do it
-        Map<Long, DsInfo> dsInfos = dataSelection.getDsInfo();
-        Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-        var length = zip ? OptionalLong.empty() : dataSelection.getFileLength();
-
-        Lock lock = null;
-        try {
-            lock = lockManager.lock(dsInfos.values(), LockType.SHARED);
-
-            if (twoLevel) {
-                checkOnline(dsInfos.values(), dataSelection.getEmptyDatasets(), dfInfos);
-            }
-            checkDatafilesPresent(dfInfos);
-
-            final boolean finalZip = zip ? true : dataSelection.mustZip();
-
-            /* Construct the name to include in the headers */
-            String name;
-            if (outname == null) {
-                if (finalZip) {
-                    name = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss").format(new Date()) + ".zip";
-                } else {
-                    name = dataSelection.getDfInfo().iterator().next().getDfName();
-                }
-            } else {
-                if (finalZip) {
-                    String ext = outname.substring(outname.lastIndexOf(".") + 1, outname.length());
-                    if ("zip".equals(ext)) {
-                        name = outname;
-                    } else {
-                        name = outname + ".zip";
-                    }
-                } else {
-                    name = outname;
-                }
-            }
-
-            Long transferId = null;
-            if (logSet.contains(CallType.READ)) {
-                try {
-                    transferId = atomicLong.getAndIncrement();
-                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                    try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                        gen.write("transferId", transferId);
-                        gen.write("userName", icat.getUserName(sessionId));
-                        addIds(gen, investigationIds, datasetIds, datafileIds);
-                        gen.writeEnd();
-                    }
-                    transmitter.processMessage("getDataStart", ip, baos.toString(), start);
-                } catch (IcatException_Exception e) {
-                    logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-                }
-            }
-
-            var response = Response.status(offset == 0 ? HttpURLConnection.HTTP_OK : HttpURLConnection.HTTP_PARTIAL)
-                    .entity(new SO(dataSelection.getDsInfo(), dataSelection.getDfInfo(), offset, finalZip, compress, lock,
-                            transferId, ip, start))
-                    .header("Content-Disposition", "attachment; filename=\"" + name + "\"").header("Accept-Ranges", "bytes");
-            length.stream()
-                    .map(l -> Math.max(0L, l - offset))
-                    .forEach(l -> response.header(CONTENT_LENGTH, l));
-            return response.build();
-        } catch (AlreadyLockedException e) {
-            logger.debug("Could not acquire lock, getData failed");
-            throw new DataNotOnlineException("Data is busy");
-        } catch (IOException e) {
-            if (lock != null) {
-                lock.release();
-            }
-            logger.error("I/O error " + e.getMessage());
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        } catch (IdsException e) {
-            lock.release();
-            throw e;
-        }
-    }
-
-    public String getDatafileIds(String preparedId, String ip)
-            throws BadRequestException, InternalException, NotFoundException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: getDatafileIds preparedId = '" + preparedId);
-
-        validateUUID("preparedId", preparedId);
-
-        // Do it
-        Prepared prepared;
-        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
-            prepared = unpack(stream);
-        } catch (NoSuchFileException e) {
-            throw new NotFoundException("The preparedId " + preparedId + " is not known");
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        final boolean zip = prepared.zip;
-        final boolean compress = prepared.compress;
-        final Set<DfInfoImpl> dfInfos = prepared.dfInfos;
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-            gen.write("zip", zip);
-            gen.write("compress", compress);
-            gen.writeStartArray("ids");
-            for (DfInfoImpl dfInfo : dfInfos) {
-                gen.write(dfInfo.getDfId());
-            }
-            gen.writeEnd().writeEnd().close();
-        }
-        String resp = baos.toString();
-
-        if (logSet.contains(CallType.INFO)) {
-            baos = new ByteArrayOutputStream();
-            try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                gen.write("preparedId", preparedId);
-                gen.writeEnd();
-            }
-            transmitter.processMessage("getDatafileIds", ip, baos.toString(), start);
-        }
-
-        return resp;
-    }
-
-    public String getDatafileIds(String sessionId, String investigationIds, String datasetIds, String datafileIds,
-                                 String ip)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info(String.format(
-                "New webservice request: getDatafileIds investigationIds=%s, datasetIds=%s, datafileIds=%s",
-                investigationIds, datasetIds, datafileIds));
-
-        validateUUID("sessionId", sessionId);
-
-        final DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                investigationIds, datasetIds, datafileIds, Returns.DATAFILES);
-
-        // Do it
-        Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-            gen.writeStartArray("ids");
-            for (DfInfoImpl dfInfo : dfInfos) {
-                gen.write(dfInfo.getDfId());
-            }
-            gen.writeEnd().writeEnd().close();
-        }
-        String resp = baos.toString();
-
-        if (logSet.contains(CallType.INFO)) {
-            baos = new ByteArrayOutputStream();
-            try {
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                transmitter.processMessage("getDatafileIds", ip, baos.toString(), start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-
-        return resp;
-
-    }
-
-    public String getIcatUrl(String ip) {
-        if (logSet.contains(CallType.INFO)) {
-            transmitter.processMessage("getIcatUrl", ip, "{}", System.currentTimeMillis());
-        }
-        return propertyHandler.getIcatUrl();
-    }
-
-    public String getServiceStatus(String sessionId, String ip)
-            throws InternalException, InsufficientPrivilegesException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: getServiceStatus");
-
-        try {
-            String uname = icat.getUserName(sessionId);
-            if (!rootUserNames.contains(uname)) {
-                throw new InsufficientPrivilegesException(uname + " is not included in the ids rootUserNames set.");
-            }
-        } catch (IcatException_Exception e) {
-            IcatExceptionType type = e.getFaultInfo().getType();
-            if (type == IcatExceptionType.SESSION) {
-                throw new InsufficientPrivilegesException(e.getClass() + " " + e.getMessage());
-            }
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        if (logSet.contains(CallType.INFO)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("getServiceStatus", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-
-        return fsm.getServiceStatus();
-    }
-
-    public long getSize(String preparedId, String ip)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: getSize preparedId = '{}'", preparedId);
-        validateUUID("preparedId", preparedId);
-
-        // Do it
-        Prepared prepared;
-        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
-            prepared = unpack(stream);
-        } catch (NoSuchFileException e) {
-            throw new NotFoundException("The preparedId " + preparedId + " is not known");
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        final Set<DfInfoImpl> dfInfos = prepared.dfInfos;
-
-        // Note that the "fast computation for the simple case" (see the other getSize() implementation) is not
-        // available when calling getSize() with a preparedId.
-        logger.debug("Slow computation for normal case");
-        String sessionId;
-        try {
-            sessionId = reader.getSessionId();
-        } catch (IcatException_Exception e) {
-            throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
-        }
-        long size = 0;
-
-        StringBuilder sb = new StringBuilder();
-        int n = 0;
-        for (DfInfoImpl df : dfInfos) {
-            if (sb.length() != 0) {
-                sb.append(',');
-            }
-            sb.append(df.getDfId());
-            if (n++ == 500) {
-                size += getSizeFor(sessionId, sb);
-                sb = new StringBuilder();
-                n = 0;
-            }
-        }
-        if (n > 0) {
-            size += getSizeFor(sessionId, sb);
-        }
-
-        if (logSet.contains(CallType.INFO)) {
-            ByteArrayOutputStream baos = new ByteArrayOutputStream();
-            try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                gen.write("preparedId", preparedId);
-                gen.writeEnd();
-            }
-            String body = baos.toString();
-            transmitter.processMessage("getSize", ip, body, start);
-        }
-
-        return size;
-    }
-
-
-    public long getSize(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info(String.format("New webservice request: getSize investigationIds=%s, datasetIds=%s, datafileIds=%s",
-                investigationIds, datasetIds, datafileIds));
-
-        validateUUID("sessionId", sessionId);
-
-        List<Long> dfids = DataSelection.getValidIds("datafileIds", datafileIds);
-        List<Long> dsids = DataSelection.getValidIds("datasetIds", datasetIds);
-        List<Long> invids = DataSelection.getValidIds("investigationIds", investigationIds);
-
-        long size = 0;
-        if (dfids.size() + dsids.size() + invids.size() == 1) {
-            size = getSizeFor(sessionId, invids, "df.dataset.investigation.id")
-                    + getSizeFor(sessionId, dsids, "df.dataset.id") + getSizeFor(sessionId, dfids, "df.id");
-            logger.debug("Fast computation for simple case");
-            if (size == 0) {
-                try {
-                    if (dfids.size() != 0) {
-                        Datafile datafile = (Datafile) icat.get(sessionId, "Datafile", dfids.get(0));
-                        if (datafile.getLocation() == null) {
-                            throw new NotFoundException("Datafile not found");
-                        }
-                    }
-                    if (dsids.size() != 0) {
-                        icat.get(sessionId, "Dataset", dsids.get(0));
-                    }
-                    if (invids.size() != 0) {
-                        icat.get(sessionId, "Investigation", invids.get(0));
-                    }
-                } catch (IcatException_Exception e) {
-                    throw new NotFoundException(e.getMessage());
-                }
-            }
-        } else {
-            logger.debug("Slow computation for normal case");
-            final DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATASETS_AND_DATAFILES);
-
-            StringBuilder sb = new StringBuilder();
-            int n = 0;
-            for (DfInfoImpl df : dataSelection.getDfInfo()) {
-                if (sb.length() != 0) {
-                    sb.append(',');
-                }
-                sb.append(df.getDfId());
-                if (n++ == 500) {
-                    size += getSizeFor(sessionId, sb);
-                    sb = new StringBuilder();
-                    n = 0;
-                }
-            }
-            if (n > 0) {
-                size += getSizeFor(sessionId, sb);
-            }
-        }
-
-        if (logSet.contains(CallType.INFO)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("getSize", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-
-        return size;
-    }
-
-    private long getSizeFor(String sessionId, List<Long> ids, String where) throws InternalException {
-
-        long size = 0;
-        if (ids != null) {
-
-            StringBuilder sb = new StringBuilder();
-            int n = 0;
-            for (Long id : ids) {
-                if (sb.length() != 0) {
-                    sb.append(',');
-                }
-                sb.append(id);
-                if (n++ == 500) {
-                    size += evalSizeFor(sessionId, where, sb);
-                    sb = new StringBuilder();
-                    n = 0;
-                }
-            }
-            if (n > 0) {
-                size += evalSizeFor(sessionId, where, sb);
-            }
-        }
-        return size;
-    }
-
-    private long getSizeFor(String sessionId, StringBuilder sb) throws InternalException {
-        String query = "SELECT SUM(df.fileSize) from Datafile df WHERE df.id IN (" + sb.toString() + ") AND df.location IS NOT NULL";
-        try {
-            return (Long) icat.search(sessionId, query).get(0);
-        } catch (IcatException_Exception e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        } catch (IndexOutOfBoundsException e) {
-            return 0L;
-        }
-    }
-
-    private long evalSizeFor(String sessionId, String where, StringBuilder sb) throws InternalException {
-        String query = "SELECT SUM(df.fileSize) from Datafile df WHERE " + where + " IN (" + sb.toString() + ") AND df.location IS NOT NULL";
-        logger.debug("icat query for size: {}", query);
-        try {
-            return (Long) icat.search(sessionId, query).get(0);
-        } catch (IcatException_Exception e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        } catch (IndexOutOfBoundsException e) {
-            return 0L;
-        }
-    }
-
-    public String getStatus(String preparedId, String ip)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: getSize preparedId = '{}'", preparedId);
-        validateUUID("preparedId", preparedId);
-
-        // Do it
-        Prepared prepared;
-        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
-            prepared = unpack(stream);
-        } catch (NoSuchFileException e) {
-            throw new NotFoundException("The preparedId " + preparedId + " is not known");
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        final Set<DfInfoImpl> dfInfos = prepared.dfInfos;
-        final Map<Long, DsInfo> dsInfos = prepared.dsInfos;
-        Set<Long> emptyDatasets = prepared.emptyDatasets;
-
-        Status status = Status.ONLINE;
-
-        if (storageUnit == StorageUnit.DATASET) {
-            Set<DsInfo> restoring = fsm.getDsRestoring();
-            Set<DsInfo> maybeOffline = fsm.getDsMaybeOffline();
-            for (DsInfo dsInfo : dsInfos.values()) {
-                fsm.checkFailure(dsInfo.getDsId());
-                if (restoring.contains(dsInfo)) {
-                    status = Status.RESTORING;
-                } else if (maybeOffline.contains(dsInfo)) {
-                    status = Status.ARCHIVED;
-                    break;
-                } else if (!emptyDatasets.contains(dsInfo.getDsId()) && !mainStorage.exists(dsInfo)) {
-                    status = Status.ARCHIVED;
-                    break;
-                }
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            Set<DfInfo> restoring = fsm.getDfRestoring();
-            Set<DfInfo> maybeOffline = fsm.getDfMaybeOffline();
-            for (DfInfo dfInfo : dfInfos) {
-                fsm.checkFailure(dfInfo.getDfId());
-                if (restoring.contains(dfInfo)) {
-                    status = Status.RESTORING;
-                } else if (maybeOffline.contains(dfInfo)) {
-                    status = Status.ARCHIVED;
-                    break;
-                } else if (!mainStorage.exists(dfInfo.getDfLocation())) {
-                    status = Status.ARCHIVED;
-                    break;
-                }
-            }
-        }
-
-        logger.debug("Status is " + status.name());
-
-        if (logSet.contains(CallType.INFO)) {
-            ByteArrayOutputStream baos = new ByteArrayOutputStream();
-            try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                gen.write("preparedId", preparedId);
-                gen.writeEnd();
-            }
-            String body = baos.toString();
-            transmitter.processMessage("getStatus", ip, body, start);
-        }
-
-        return status.name();
-
-    }
-
-    public String getStatus(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info(
-                String.format("New webservice request: getStatus investigationIds=%s, datasetIds=%s, datafileIds=%s",
-                        investigationIds, datasetIds, datafileIds));
-
-        if (sessionId == null) {
-            try {
-                sessionId = reader.getSessionId();
-            } catch (IcatException_Exception e) {
-                throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
-            }
-        } else {
-            validateUUID("sessionId", sessionId);
-        }
-
-        // Do it
-        Status status = Status.ONLINE;
-
-        if (storageUnit == StorageUnit.DATASET) {
-            DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATASETS);
-            Map<Long, DsInfo> dsInfos = dataSelection.getDsInfo();
-
-            Set<DsInfo> restoring = fsm.getDsRestoring();
-            Set<DsInfo> maybeOffline = fsm.getDsMaybeOffline();
-            Set<Long> emptyDatasets = dataSelection.getEmptyDatasets();
-            for (DsInfo dsInfo : dsInfos.values()) {
-                fsm.checkFailure(dsInfo.getDsId());
-                if (restoring.contains(dsInfo)) {
-                    status = Status.RESTORING;
-                } else if (maybeOffline.contains(dsInfo)) {
-                    status = Status.ARCHIVED;
-                    break;
-                } else if (!emptyDatasets.contains(dsInfo.getDsId()) && !mainStorage.exists(dsInfo)) {
-                    status = Status.ARCHIVED;
-                    break;
-                }
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATAFILES);
-            Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-
-            Set<DfInfo> restoring = fsm.getDfRestoring();
-            Set<DfInfo> maybeOffline = fsm.getDfMaybeOffline();
-            for (DfInfo dfInfo : dfInfos) {
-                fsm.checkFailure(dfInfo.getDfId());
-                if (restoring.contains(dfInfo)) {
-                    status = Status.RESTORING;
-                } else if (maybeOffline.contains(dfInfo)) {
-                    status = Status.ARCHIVED;
-                    break;
-                } else if (!mainStorage.exists(dfInfo.getDfLocation())) {
-                    status = Status.ARCHIVED;
-                    break;
-                }
-            }
-        } else {
-            // Throw exception if selection does not exist
-            new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATASETS);
-        }
-
-        logger.debug("Status is " + status.name());
-
-        if (logSet.contains(CallType.INFO)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    if (sessionId != null) {
-                        gen.write("userName", icat.getUserName(sessionId));
-                    }
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("getStatus", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-
-        return status.name();
-
-    }
-
-    @PostConstruct
-    private void init() {
-        try {
-            synchronized (inited) {
-                logger.info("creating IdsBean");
-                propertyHandler = PropertyHandler.getInstance();
-                zipMapper = propertyHandler.getZipMapper();
-                mainStorage = propertyHandler.getMainStorage();
-                archiveStorage = propertyHandler.getArchiveStorage();
-                twoLevel = archiveStorage != null;
-                datatypeFactory = DatatypeFactory.newInstance();
-                preparedDir = propertyHandler.getCacheDir().resolve("prepared");
-                Files.createDirectories(preparedDir);
-
-                rootUserNames = propertyHandler.getRootUserNames();
-                readOnly = propertyHandler.getReadOnly();
-                enableWrite = propertyHandler.getEnableWrite();
-
-                icat = propertyHandler.getIcatService();
-
-                if (!inited) {
-                    key = propertyHandler.getKey();
-                    logger.info("Key is " + (key == null ? "not set" : "set"));
-                }
-
-                if (twoLevel) {
-                    storageUnit = propertyHandler.getStorageUnit();
-                    datasetDir = propertyHandler.getCacheDir().resolve("dataset");
-                    markerDir = propertyHandler.getCacheDir().resolve("marker");
-                    if (!inited) {
-                        Files.createDirectories(datasetDir);
-                        Files.createDirectories(markerDir);
-                        restartUnfinishedWork();
-                    }
-                }
-
-                if (!inited) {
-                    cleanPreparedDir(preparedDir);
-                    if (twoLevel) {
-                        cleanDatasetCache(datasetDir);
-                    }
-                }
-
-                maxIdsInQuery = propertyHandler.getMaxIdsInQuery();
-
-                threadPool = Executors.newCachedThreadPool();
-
-                logSet = propertyHandler.getLogSet();
-
-                inited = true;
-
-                logger.info("created IdsBean");
-            }
-        } catch (Throwable e) {
-            logger.error("Won't start ", e);
-            throw new RuntimeException("IdsBean reports " + e.getClass() + " " + e.getMessage());
-        }
-    }
-
-    public Boolean isPrepared(String preparedId, String ip)
-            throws BadRequestException, NotFoundException, InternalException {
-
-        long start = System.currentTimeMillis();
-
-        logger.info(String.format("New webservice request: isPrepared preparedId=%s", preparedId));
-
-        // Validate
-        validateUUID("preparedId", preparedId);
-
-        // Do it
-        boolean prepared = true;
-
-        Prepared preparedJson;
-        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
-            preparedJson = unpack(stream);
-        } catch (NoSuchFileException e) {
-            throw new NotFoundException("The preparedId " + preparedId + " is not known");
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        PreparedStatus status = preparedStatusMap.computeIfAbsent(preparedId, k -> new PreparedStatus());
-
-        if (!status.lock.tryLock()) {
-            logger.debug("Lock held for evaluation of isPrepared for preparedId {}", preparedId);
-            return false;
-        }
-        try {
-            Future<?> future = status.future;
-            if (future != null) {
-                if (future.isDone()) {
-                    try {
-                        future.get();
-                    } catch (ExecutionException e) {
-                        throw new InternalException(e.getClass() + " " + e.getMessage());
-                    } catch (InterruptedException e) {
-                        // Ignore
-                    } finally {
-                        status.future = null;
-                    }
-                } else {
-                    logger.debug("Background process still running for preparedId {}", preparedId);
-                    return false;
-                }
-            }
-
-            if (storageUnit == StorageUnit.DATASET) {
-                Collection<DsInfo> toCheck = status.fromDsElement == null ? preparedJson.dsInfos.values()
-                        : preparedJson.dsInfos.tailMap(status.fromDsElement).values();
-                logger.debug("Will check online status of {} entries", toCheck.size());
-                for (DsInfo dsInfo : toCheck) {
-                    fsm.checkFailure(dsInfo.getDsId());
-                    if (restoreIfOffline(dsInfo, preparedJson.emptyDatasets)) {
-                        prepared = false;
-                        status.fromDsElement = dsInfo.getDsId();
-                        toCheck = preparedJson.dsInfos.tailMap(status.fromDsElement).values();
-                        logger.debug("Will check in background status of {} entries", toCheck.size());
-                        status.future = threadPool.submit(new RunPrepDsCheck(toCheck, preparedJson.emptyDatasets));
-                        break;
-                    }
-                }
-                if (prepared) {
-                    toCheck = status.fromDsElement == null ? Collections.emptySet()
-                            : preparedJson.dsInfos.headMap(status.fromDsElement).values();
-                    logger.debug("Will check finally online status of {} entries", toCheck.size());
-                    for (DsInfo dsInfo : toCheck) {
-                        fsm.checkFailure(dsInfo.getDsId());
-                        if (restoreIfOffline(dsInfo, preparedJson.emptyDatasets)) {
-                            prepared = false;
-                        }
-                    }
-                }
-            } else if (storageUnit == StorageUnit.DATAFILE) {
-                SortedSet<DfInfoImpl> toCheck = status.fromDfElement == null ? preparedJson.dfInfos
-                        : preparedJson.dfInfos.tailSet(status.fromDfElement);
-                logger.debug("Will check online status of {} entries", toCheck.size());
-                for (DfInfoImpl dfInfo : toCheck) {
-                    fsm.checkFailure(dfInfo.getDfId());
-                    if (restoreIfOffline(dfInfo)) {
-                        prepared = false;
-                        status.fromDfElement = dfInfo;
-                        toCheck = preparedJson.dfInfos.tailSet(status.fromDfElement);
-                        logger.debug("Will check in background status of {} entries", toCheck.size());
-                        status.future = threadPool.submit(new RunPrepDfCheck(toCheck));
-                        break;
-                    }
-                }
-                if (prepared) {
-                    toCheck = status.fromDfElement == null ? new TreeSet<>()
-                            : preparedJson.dfInfos.headSet(status.fromDfElement);
-                    logger.debug("Will check finally online status of {} entries", toCheck.size());
-                    for (DfInfoImpl dfInfo : toCheck) {
-                        fsm.checkFailure(dfInfo.getDfId());
-                        if (restoreIfOffline(dfInfo)) {
-                            prepared = false;
-                        }
-                    }
-                }
-            }
-
-            if (logSet.contains(CallType.INFO)) {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("preparedId", preparedId);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("isPrepared", ip, body, start);
-            }
-
-            return prepared;
-
-        } finally {
-            status.lock.unlock();
-        }
-
-    }
-
-    public boolean isReadOnly(String ip) {
-        if (logSet.contains(CallType.INFO)) {
-            transmitter.processMessage("isReadOnly", ip, "{}", System.currentTimeMillis());
-        }
-        return readOnly;
-    }
-
-    public boolean isTwoLevel(String ip) {
-        if (logSet.contains(CallType.INFO)) {
-            transmitter.processMessage("isTwoLevel", ip, "{}", System.currentTimeMillis());
-        }
-        return twoLevel;
-    }
-
-    public String prepareData(String sessionId, String investigationIds, String datasetIds, String datafileIds,
-                              boolean compress, boolean zip, String ip)
-            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: prepareData " + "investigationIds='" + investigationIds + "' "
-                + "datasetIds='" + datasetIds + "' " + "datafileIds='" + datafileIds + "' " + "compress='" + compress
-                + "' " + "zip='" + zip + "'");
-
-        validateUUID("sessionId", sessionId);
-
-        final DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                investigationIds, datasetIds, datafileIds, Returns.DATASETS_AND_DATAFILES);
-
-        // Do it
-        String preparedId = UUID.randomUUID().toString();
-
-        Map<Long, DsInfo> dsInfos = dataSelection.getDsInfo();
-        Set<Long> emptyDs = dataSelection.getEmptyDatasets();
-        Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-
-        if (storageUnit == StorageUnit.DATASET) {
-            for (DsInfo dsInfo : dsInfos.values()) {
-                fsm.recordSuccess(dsInfo.getDsId());
-            }
-            threadPool.submit(new RestoreDsTask(dsInfos.values(), emptyDs));
-
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            for (DfInfo dfInfo : dfInfos) {
-                fsm.recordSuccess(dfInfo.getDfId());
-            }
-            threadPool.submit(new RestoreDfTask(dfInfos));
-        }
-
-        if (dataSelection.mustZip()) {
-            zip = true;
-        }
-
-        logger.debug("Writing to " + preparedDir.resolve(preparedId));
-        try (OutputStream stream = new BufferedOutputStream(Files.newOutputStream(preparedDir.resolve(preparedId)))) {
-            pack(stream, zip, compress, dsInfos, dfInfos, emptyDs);
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        logger.debug("preparedId is " + preparedId);
-
-        if (logSet.contains(CallType.PREPARE)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.write("preparedId", preparedId);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("prepareData", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-
-        return preparedId;
-    }
-
-    public Response put(InputStream body, String sessionId, String name, String datafileFormatIdString,
-                        String datasetIdString, String description, String doi, String datafileCreateTimeString,
-                        String datafileModTimeString, boolean wrap, boolean padding, String ip)
-            throws NotFoundException, DataNotOnlineException, BadRequestException, InsufficientPrivilegesException,
-            InternalException, NotImplementedException {
-
-        long start = System.currentTimeMillis();
-
-        try {
-            // Log and validate
-            logger.info("New webservice request: put " + "name='" + name + "' " + "datafileFormatId='"
-                    + datafileFormatIdString + "' " + "datasetId='" + datasetIdString + "' " + "description='"
-                    + description + "' " + "doi='" + doi + "' " + "datafileCreateTime='" + datafileCreateTimeString
-                    + "' " + "datafileModTime='" + datafileModTimeString + "'");
-
-            if (readOnly) {
-                throw new NotImplementedException("This operation has been configured to be unavailable");
-            }
-
-            IdsBean.validateUUID("sessionId", sessionId);
-            if (name == null) {
-                throw new BadRequestException("The name parameter must be set");
-            }
-
-            if (datafileFormatIdString == null) {
-                throw new BadRequestException("The datafileFormatId parameter must be set");
-            }
-            long datafileFormatId;
-            try {
-                datafileFormatId = Long.parseLong(datafileFormatIdString);
-            } catch (NumberFormatException e) {
-                throw new BadRequestException("The datafileFormatId parameter must be numeric");
-            }
-
-            if (datasetIdString == null) {
-                throw new BadRequestException("The datasetId parameter must be set");
-            }
-            long datasetId;
-            try {
-                datasetId = Long.parseLong(datasetIdString);
-            } catch (NumberFormatException e) {
-                throw new BadRequestException("The datasetId parameter must be numeric");
-            }
-
-            Long datafileCreateTime = null;
-            if (datafileCreateTimeString != null) {
-                try {
-                    datafileCreateTime = Long.parseLong(datafileCreateTimeString);
-                } catch (NumberFormatException e) {
-                    throw new BadRequestException("The datafileCreateTime parameter must be numeric");
-                }
-            }
-
-            Long datafileModTime = null;
-            if (datafileModTimeString != null) {
-                try {
-                    datafileModTime = Long.parseLong(datafileModTimeString);
-                } catch (NumberFormatException e) {
-                    throw new BadRequestException("The datafileModTime parameter must be numeric");
-                }
-            }
-
-            // Do it
-            Dataset ds;
-            try {
-                ds = (Dataset) icat.get(sessionId, "Dataset INCLUDE Investigation, Facility", datasetId);
-            } catch (IcatException_Exception e) {
-                IcatExceptionType type = e.getFaultInfo().getType();
-                if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
-                    throw new InsufficientPrivilegesException(e.getMessage());
-                }
-                if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
-                    throw new NotFoundException(e.getMessage());
-                }
-                throw new InternalException(type + " " + e.getMessage());
-            }
-
-            DsInfo dsInfo = new DsInfoImpl(ds);
-            try (Lock lock = lockManager.lock(dsInfo, LockType.SHARED)) {
-                if (storageUnit == StorageUnit.DATASET) {
-                    Set<DfInfoImpl> dfInfos = Collections.emptySet();
-                    Set<Long> emptyDatasets = new HashSet<>();
-                    try {
-                        List<Object> counts = icat.search(sessionId,
-                                "COUNT(Datafile) <-> Dataset [id=" + dsInfo.getDsId() + "]");
-                        if ((Long) counts.get(0) == 0) {
-                            emptyDatasets.add(dsInfo.getDsId());
-                        }
-                    } catch (IcatException_Exception e) {
-                        IcatExceptionType type = e.getFaultInfo().getType();
-                        if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
-                            throw new InsufficientPrivilegesException(e.getMessage());
-                        }
-                        if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
-                            throw new NotFoundException(e.getMessage());
-                        }
-                        throw new InternalException(type + " " + e.getMessage());
-                    }
-                    Set<DsInfo> dsInfos = new HashSet<>();
-                    dsInfos.add(dsInfo);
-                    checkOnline(dsInfos, emptyDatasets, dfInfos);
-                }
-
-                CRC32 crc = new CRC32();
-                CheckedWithSizeInputStream is = new CheckedWithSizeInputStream(body, crc);
-                String location;
-                try {
-                    location = mainStorage.put(dsInfo, name, is);
-                } catch (IllegalArgumentException e) {
-                    throw new BadRequestException("Illegal filename or dataset: " + e.getMessage());
-                }
-                is.close();
-                long checksum = crc.getValue();
-                long size = is.getSize();
-                Long dfId;
-                try {
-                    dfId = registerDatafile(sessionId, name, datafileFormatId, location, checksum, size, ds,
-                            description, doi, datafileCreateTime, datafileModTime);
-                } catch (InsufficientPrivilegesException | NotFoundException | InternalException
-                         | BadRequestException e) {
-                    logger.debug("Problem with registration " + e.getClass() + " " + e.getMessage()
-                            + " datafile will now be deleted");
-                    String userId = null;
-                    try {
-                        userId = icat.getUserName(sessionId);
-                    } catch (IcatException_Exception e1) {
-                        logger.error("Unable to get user name for session " + sessionId + " so mainStorage.delete of "
-                                + location + " may fail");
-                    }
-                    mainStorage.delete(location, userId, userId);
-                    throw e;
-                }
-
-                if (storageUnit == StorageUnit.DATASET) {
-                    fsm.queue(dsInfo, DeferredOp.WRITE);
-                } else if (storageUnit == StorageUnit.DATAFILE) {
-                    Datafile df;
-                    try {
-                        df = (Datafile) reader.get("Datafile", dfId);
-                    } catch (IcatException_Exception e) {
-                        throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
-                    }
-                    fsm.queue(new DfInfoImpl(dfId, name, location, df.getCreateId(), df.getModId(), dsInfo.getDsId()),
-                            DeferredOp.WRITE);
-                }
-
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                Json.createGenerator(baos).writeStartObject().write("id", dfId).write("checksum", checksum)
-                        .write("location", location.replace("\\", "\\\\").replace("'", "\\'")).write("size", size)
-                        .writeEnd().close();
-                String resp = wrap ? prefix + baos.toString() + suffix : baos.toString();
-
-                if (logSet.contains(CallType.WRITE)) {
-                    try {
-                        baos = new ByteArrayOutputStream();
-                        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                            gen.write("userName", icat.getUserName(sessionId));
-                            gen.write("datafileId", dfId);
-                            gen.writeEnd();
-                        }
-                        transmitter.processMessage("put", ip, baos.toString(), start);
-                    } catch (IcatException_Exception e) {
-                        logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-                    }
-                }
-
-                return Response.status(HttpURLConnection.HTTP_CREATED).entity(resp).build();
-
-            } catch (AlreadyLockedException e) {
-                logger.debug("Could not acquire lock, put failed");
-                throw new DataNotOnlineException("Data is busy");
-            } catch (IOException e) {
-                logger.error("I/O exception " + e.getMessage() + " putting " + name + " to Dataset with id "
-                        + datasetIdString);
-                throw new InternalException(e.getClass() + " " + e.getMessage());
-            }
-        } catch (IdsException e) {
-
-            ByteArrayOutputStream baos = new ByteArrayOutputStream();
-            JsonGenerator gen = Json.createGenerator(baos);
-            gen.writeStartObject().write("code", e.getClass().getSimpleName()).write("message", e.getShortMessage());
-            gen.writeEnd().close();
-            if (wrap) {
-                String pre = padding ? paddedPrefix : prefix;
-                return Response.status(e.getHttpStatusCode()).entity(pre + baos.toString().replace("'", "\\'") + suffix)
-                        .build();
-            } else {
-                return Response.status(e.getHttpStatusCode()).entity(baos.toString()).build();
-            }
-        }
-
-    }
-
-    private Long registerDatafile(String sessionId, String name, long datafileFormatId, String location, long checksum,
-                                  long size, Dataset dataset, String description, String doi, Long datafileCreateTime, Long datafileModTime)
-            throws InsufficientPrivilegesException, NotFoundException, InternalException, BadRequestException {
-        final Datafile df = new Datafile();
-        DatafileFormat format;
-        try {
-            format = (DatafileFormat) icat.get(sessionId, "DatafileFormat", datafileFormatId);
-        } catch (IcatException_Exception e) {
-            IcatExceptionType type = e.getFaultInfo().getType();
-            if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
-                throw new InsufficientPrivilegesException(e.getMessage());
-            }
-            if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
-                throw new NotFoundException(e.getMessage());
-            }
-            throw new InternalException(type + " " + e.getMessage());
-        }
-
-        df.setDatafileFormat(format);
-        df.setLocation(location);
-        df.setFileSize(size);
-        df.setChecksum(Long.toHexString(checksum));
-        df.setName(name);
-        df.setDataset(dataset);
-        df.setDescription(description);
-        df.setDoi(doi);
-        if (datafileCreateTime != null) {
-            GregorianCalendar gregorianCalendar = new GregorianCalendar();
-            gregorianCalendar.setTimeInMillis(datafileCreateTime);
-            df.setDatafileCreateTime(datatypeFactory.newXMLGregorianCalendar(gregorianCalendar));
-        }
-        if (datafileModTime != null) {
-            GregorianCalendar gregorianCalendar = new GregorianCalendar();
-            gregorianCalendar.setTimeInMillis(datafileModTime);
-            df.setDatafileModTime(datatypeFactory.newXMLGregorianCalendar(gregorianCalendar));
-        }
-        try {
-            long dfId = icat.create(sessionId, df);
-            df.setId(dfId);
-
-            if (key != null) {
-                df.setLocation(location + " " + IcatSecurity.digest(dfId, location, key));
-                icat.update(sessionId, df);
-            }
-
-            logger.debug("Registered datafile for dataset {} for {}", dataset.getId(), name + " at " + location);
-            return dfId;
-        } catch (IcatException_Exception e) {
-            IcatExceptionType type = e.getFaultInfo().getType();
-            if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
-                throw new InsufficientPrivilegesException(e.getMessage());
-            }
-            if (type == IcatExceptionType.VALIDATION) {
-                throw new BadRequestException(e.getMessage());
-            }
-            throw new InternalException(type + " " + e.getMessage());
-        } catch (NoSuchAlgorithmException e) {
-            throw new InternalException(e.getMessage());
-        }
-    }
-
-    public void reset(String preparedId, String ip) throws BadRequestException, InternalException, NotFoundException {
-        long start = System.currentTimeMillis();
-
-        logger.info(String.format("New webservice request: reset preparedId=%s", preparedId));
-
-        // Validate
-        validateUUID("preparedId", preparedId);
-
-        // Do it
-        Prepared preparedJson;
-        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
-            preparedJson = unpack(stream);
-        } catch (NoSuchFileException e) {
-            throw new NotFoundException("The preparedId " + preparedId + " is not known");
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        if (storageUnit == StorageUnit.DATASET) {
-            for (DsInfo dsInfo : preparedJson.dsInfos.values()) {
-                fsm.recordSuccess(dsInfo.getDsId());
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            for (DfInfoImpl dfInfo : preparedJson.dfInfos) {
-                fsm.recordSuccess(dfInfo.getDfId());
-            }
-        }
-
-        if (logSet.contains(CallType.MIGRATE)) {
-            ByteArrayOutputStream baos = new ByteArrayOutputStream();
-            try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                gen.write("preparedId", preparedId);
-                gen.writeEnd();
-            }
-            String body = baos.toString();
-            transmitter.processMessage("reset", ip, body, start);
-        }
-    }
-
-    public void reset(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: reset " + "investigationIds='" + investigationIds + "' " + "datasetIds='"
-                + datasetIds + "' " + "datafileIds='" + datafileIds + "'");
-
-        validateUUID("sessionId", sessionId);
-
-        final DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                investigationIds, datasetIds, datafileIds, Returns.DATASETS_AND_DATAFILES);
-
-        // Do it
-        if (storageUnit == StorageUnit.DATASET) {
-            for (DsInfo dsInfo : dataSelection.getDsInfo().values()) {
-                fsm.recordSuccess(dsInfo.getDsId());
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            for (DfInfoImpl dfInfo : dataSelection.getDfInfo()) {
-                fsm.recordSuccess(dfInfo.getDfId());
-            }
-        }
-
-        if (logSet.contains(CallType.MIGRATE)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                String body = baos.toString();
-                transmitter.processMessage("reset", ip, body, start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-    }
-
-    private void restartUnfinishedWork() throws InternalException {
-
-        try {
-            for (File file : markerDir.toFile().listFiles()) {
-                if (storageUnit == StorageUnit.DATASET) {
-                    long dsid = Long.parseLong(file.toPath().getFileName().toString());
-                    Dataset ds = null;
-                    try {
-                        ds = (Dataset) reader.get("Dataset ds INCLUDE ds.investigation.facility", dsid);
-                        DsInfo dsInfo = new DsInfoImpl(ds);
-                        fsm.queue(dsInfo, DeferredOp.WRITE);
-                        logger.info("Queued dataset with id " + dsid + " " + dsInfo
-                                + " to be written as it was not written out previously by IDS");
-                    } catch (IcatException_Exception e) {
-                        if (e.getFaultInfo().getType() == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
-                            logger.warn("Dataset with id " + dsid
-                                    + " was not written out by IDS and now no longer known to ICAT");
-                            Files.delete(file.toPath());
-                        } else {
-                            throw e;
-                        }
-                    }
-                } else if (storageUnit == StorageUnit.DATAFILE) {
-                    long dfid = Long.parseLong(file.toPath().getFileName().toString());
-                    Datafile df = null;
-                    try {
-                        df = (Datafile) reader.get("Datafile ds INCLUDE ds.dataset", dfid);
-                        String location = getLocation(df.getId(), df.getLocation());
-                        DfInfoImpl dfInfo = new DfInfoImpl(dfid, df.getName(), location, df.getCreateId(),
-                                df.getModId(), df.getDataset().getId());
-                        fsm.queue(dfInfo, DeferredOp.WRITE);
-                        logger.info("Queued datafile with id " + dfid + " " + dfInfo
-                                + " to be written as it was not written out previously by IDS");
-                    } catch (IcatException_Exception e) {
-                        if (e.getFaultInfo().getType() == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
-                            logger.warn("Datafile with id " + dfid
-                                    + " was not written out by IDS and now no longer known to ICAT");
-                            Files.delete(file.toPath());
-                        } else {
-                            throw e;
-                        }
-                    }
-                }
-            }
-        } catch (Exception e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-    }
-
-    public void restore(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
-            NotFoundException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: restore " + "investigationIds='" + investigationIds + "' " + "datasetIds='"
-                + datasetIds + "' " + "datafileIds='" + datafileIds + "'");
-
-        validateUUID("sessionId", sessionId);
-
-        // Do it
-        if (storageUnit == StorageUnit.DATASET) {
-            DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATASETS);
-            Map<Long, DsInfo> dsInfos = dataSelection.getDsInfo();
-            for (DsInfo dsInfo : dsInfos.values()) {
-                fsm.queue(dsInfo, DeferredOp.RESTORE);
-            }
-        } else if (storageUnit == StorageUnit.DATAFILE) {
-            DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                    investigationIds, datasetIds, datafileIds, Returns.DATAFILES);
-            Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-            for (DfInfoImpl dfInfo : dfInfos) {
-                fsm.queue(dfInfo, DeferredOp.RESTORE);
-            }
-        } else {
-            throw new NotImplementedException("This operation is unavailable for single level storage");
-        }
-
-        if (logSet.contains(CallType.MIGRATE)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                transmitter.processMessage("restore", ip, baos.toString(), start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-    }
-
-    private boolean restoreIfOffline(DfInfoImpl dfInfo) throws InternalException {
-        boolean maybeOffline = false;
-        if (fsm.getDfMaybeOffline().contains(dfInfo)) {
-            maybeOffline = true;
-        } else if (!mainStorage.exists(dfInfo.getDfLocation())) {
-            fsm.queue(dfInfo, DeferredOp.RESTORE);
-            maybeOffline = true;
-        }
-        return maybeOffline;
-    }
-
-    private boolean restoreIfOffline(DsInfo dsInfo, Set<Long> emptyDatasets) throws InternalException {
-        boolean maybeOffline = false;
-        if (fsm.getDsMaybeOffline().contains(dsInfo)) {
-            maybeOffline = true;
-        } else if (!emptyDatasets.contains(dsInfo.getDsId()) && !mainStorage.exists(dsInfo)) {
-            fsm.queue(dsInfo, DeferredOp.RESTORE);
-            maybeOffline = true;
-        }
-        return maybeOffline;
-    }
-
-    public void write(String sessionId, String investigationIds, String datasetIds, String datafileIds, String ip)
-            throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
-            NotFoundException, DataNotOnlineException {
-
-        long start = System.currentTimeMillis();
-
-        // Log and validate
-        logger.info("New webservice request: write " + "investigationIds='" + investigationIds + "' " + "datasetIds='"
-                + datasetIds + "' " + "datafileIds='" + datafileIds + "'");
-
-        if (!enableWrite) {
-            throw new NotImplementedException("This operation has been configured to be unavailable");
-        }
-
-        validateUUID("sessionId", sessionId);
-
-        final DataSelection dataSelection = new DataSelection(propertyHandler, reader, sessionId,
-                investigationIds, datasetIds, datafileIds, Returns.DATASETS_AND_DATAFILES);
-
-        // Do it
-        Map<Long, DsInfo> dsInfos = dataSelection.getDsInfo();
-        Set<DfInfoImpl> dfInfos = dataSelection.getDfInfo();
-
-        try (Lock lock = lockManager.lock(dsInfos.values(), LockType.SHARED)) {
-            if (twoLevel) {
-                boolean maybeOffline = false;
-                if (storageUnit == StorageUnit.DATASET) {
-                    for (DsInfo dsInfo : dsInfos.values()) {
-                        if (!dataSelection.getEmptyDatasets().contains(dsInfo.getDsId()) &&
-                                !mainStorage.exists(dsInfo)) {
-                            maybeOffline = true;
-                        }
-                    }
-                } else if (storageUnit == StorageUnit.DATAFILE) {
-                    for (DfInfoImpl dfInfo : dfInfos) {
-                        if (!mainStorage.exists(dfInfo.getDfLocation())) {
-                            maybeOffline = true;
-                        }
-                    }
-                }
-                if (maybeOffline) {
-                    throw new DataNotOnlineException("Requested data is not online, write request refused");
-                }
-            }
-
-            if (storageUnit == StorageUnit.DATASET) {
-                for (DsInfo dsInfo : dsInfos.values()) {
-                    fsm.queue(dsInfo, DeferredOp.WRITE);
-                }
-            } else if (storageUnit == StorageUnit.DATAFILE) {
-                for (DfInfoImpl dfInfo : dfInfos) {
-                    fsm.queue(dfInfo, DeferredOp.WRITE);
-                }
-            } else {
-                throw new NotImplementedException("This operation is unavailable for single level storage");
-            }
-        } catch (AlreadyLockedException e) {
-            logger.debug("Could not acquire lock, write failed");
-            throw new DataNotOnlineException("Data is busy");
-        } catch (IOException e) {
-            logger.error("I/O error " + e.getMessage() + " writing");
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        }
-
-        if (logSet.contains(CallType.MIGRATE)) {
-            try {
-                ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
-                    gen.write("userName", icat.getUserName(sessionId));
-                    addIds(gen, investigationIds, datasetIds, datafileIds);
-                    gen.writeEnd();
-                }
-                transmitter.processMessage("write", ip, baos.toString(), start);
-            } catch (IcatException_Exception e) {
-                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
-            }
-        }
-    }
-}
diff --git a/src/main/java/org/icatproject/ids/IdsService.java b/src/main/java/org/icatproject/ids/IdsService.java
index 804e24b9..92235972 100644
--- a/src/main/java/org/icatproject/ids/IdsService.java
+++ b/src/main/java/org/icatproject/ids/IdsService.java
@@ -4,8 +4,8 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
+import java.nio.file.Files;
+
 
 import jakarta.annotation.PostConstruct;
 import jakarta.annotation.PreDestroy;
@@ -23,22 +23,49 @@
 import jakarta.ws.rs.HeaderParam;
 import jakarta.ws.rs.POST;
 import jakarta.ws.rs.PUT;
-import jakarta.ws.rs.Path;
 import jakarta.ws.rs.Produces;
 import jakarta.ws.rs.QueryParam;
 import jakarta.ws.rs.core.Context;
 import jakarta.ws.rs.core.MediaType;
 import jakarta.ws.rs.core.Response;
+import jakarta.ws.rs.Path;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.RequestIdNames;
 import org.icatproject.ids.exceptions.BadRequestException;
 import org.icatproject.ids.exceptions.DataNotOnlineException;
 import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
 import org.icatproject.ids.exceptions.InternalException;
 import org.icatproject.ids.exceptions.NotFoundException;
 import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.helpers.Constants;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.ArchiveHandler;
+import org.icatproject.ids.requestHandlers.DeleteHandler;
+import org.icatproject.ids.requestHandlers.GetDataFileIdsHandler;
+import org.icatproject.ids.requestHandlers.GetDataHandler;
+import org.icatproject.ids.requestHandlers.GetIcatUrlHandler;
+import org.icatproject.ids.requestHandlers.GetServiceStatusHandler;
+import org.icatproject.ids.requestHandlers.GetStatusHandler;
+import org.icatproject.ids.requestHandlers.IsPreparedHandler;
+import org.icatproject.ids.requestHandlers.IsReadOnlyHandler;
+import org.icatproject.ids.requestHandlers.IsTwoLevelHandler;
+import org.icatproject.ids.requestHandlers.PrepareDataHandler;
+import org.icatproject.ids.requestHandlers.PutHandler;
+import org.icatproject.ids.requestHandlers.ResetHandler;
+import org.icatproject.ids.requestHandlers.RestoreHandler;
+import org.icatproject.ids.requestHandlers.WriteHandler;
+import org.icatproject.ids.requestHandlers.getSizeHandlers.GetSizeHandler;
+import org.icatproject.ids.requestHandlers.getSizeHandlers.GetSizeHandlerForFastProcessing;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.Transmitter;
+import org.icatproject.ids.services.UnfinishedWorkService;
 
 @Path("/")
 @Stateless
@@ -47,9 +74,79 @@ public class IdsService {
     private final static Logger logger = LoggerFactory.getLogger(IdsService.class);
 
     @EJB
-    private IdsBean idsBean;
+    Transmitter transmitter;
+
+    @EJB
+    private LockManager lockManager;
+
+    @EJB
+    private IcatReader reader;
+
+    private FiniteStateMachine fsm = null;
+
+    private static Boolean inited = false;
+    private final Object lock = new Object();
+
+    private UnfinishedWorkService unfinishedWorkService;
+
+
+    @PostConstruct
+    private void init() {
+
+        try {
+            synchronized (lock) {
+
+                logger.info("creating IdsService");
+
+                FiniteStateMachine.createInstance(reader, lockManager, PropertyHandler.getInstance().getStorageUnit());
+                this.fsm = FiniteStateMachine.getInstance();
+                this.fsm.init();
+                ServiceProvider.createInstance(transmitter, fsm, lockManager, reader);
+
+                var propertyHandler = ServiceProvider.getInstance().getPropertyHandler();
+                var archiveStorage = propertyHandler.getArchiveStorage();
+                var twoLevel = archiveStorage != null;
+                var preparedDir = propertyHandler.getCacheDir().resolve("prepared");
+
+                Files.createDirectories(preparedDir);
+                this.unfinishedWorkService = new UnfinishedWorkService();
+
+                String key = "";
+                if (!inited) {
+                    key = propertyHandler.getKey();
+                    logger.info("Key is " + (key == null ? "not set" : "set"));
+                    this.unfinishedWorkService.cleanPreparedDir(preparedDir);
+                }
+
+                java.nio.file.Path datasetDir;
+                if (twoLevel) {
+                    datasetDir = propertyHandler.getCacheDir().resolve("dataset");
+                    var markerDir = propertyHandler.getCacheDir().resolve("marker");
+                    if (!inited) {
+                        Files.createDirectories(datasetDir);
+                        Files.createDirectories(markerDir);
+                        this.unfinishedWorkService.restartUnfinishedWork(markerDir, key);
+                        this.unfinishedWorkService.cleanDatasetCache(datasetDir);
+                    }
+                }
+
+                inited = true;
+
+                logger.info("created IdsService");
+            }
+        } catch (Throwable e) {
+            logger.error("Won't start ", e);
+            throw new RuntimeException("IdsService reports " + e.getClass() + " " + e.getMessage());
+        }
+    }
+
+
+    @PreDestroy
+    private void exit() {
+        this.fsm.exit();
+        logger.info("destroyed IdsService");
+    }
 
-    private Pattern rangeRe;
 
     /**
      * Archive data specified by the investigationIds, datasetIds and
@@ -67,17 +164,20 @@ public class IdsService {
      * @throws InsufficientPrivilegesException
      * @throws InternalException
      * @throws NotFoundException
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @POST
     @Path("archive")
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
-    public void archive(@Context HttpServletRequest request, @FormParam("sessionId") String sessionId,
+    public void archive(@Context HttpServletRequest request, @FormParam(RequestIdNames.sessionId) String sessionId,
                         @FormParam("investigationIds") String investigationIds, @FormParam("datasetIds") String datasetIds,
                         @FormParam("datafileIds") String datafileIds)
             throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
-            NotFoundException {
-        idsBean.archive(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
+            NotFoundException, DataNotOnlineException {
+
+        var handler = new ArchiveHandler(request.getRemoteAddr(), sessionId, investigationIds, datasetIds, datafileIds);
+        handler.handle();
     }
 
     /**
@@ -100,18 +200,16 @@ public void archive(@Context HttpServletRequest request, @FormParam("sessionId")
      */
     @DELETE
     @Path("delete")
-    public void delete(@Context HttpServletRequest request, @QueryParam("sessionId") String sessionId,
+    public void delete(@Context HttpServletRequest request, @QueryParam(RequestIdNames.sessionId) String sessionId,
                        @QueryParam("investigationIds") String investigationIds, @QueryParam("datasetIds") String datasetIds,
                        @QueryParam("datafileIds") String datafileIds) throws NotImplementedException, BadRequestException,
             InsufficientPrivilegesException, NotFoundException, InternalException, DataNotOnlineException {
-        idsBean.delete(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
-    }
 
-    @PreDestroy
-    private void exit() {
-        logger.info("destroyed IdsService");
+        var handler = new DeleteHandler(request.getRemoteAddr(), sessionId, investigationIds, datasetIds, datafileIds);
+        handler.handle();
     }
 
+
     /**
      * Return the version of the server
      *
@@ -159,37 +257,21 @@ public String getVersion() {
      * @throws InternalException
      * @throws InsufficientPrivilegesException
      * @throws DataNotOnlineException
+     * @throws NotImplementedException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("getData")
     @Produces(MediaType.APPLICATION_OCTET_STREAM)
-    public Response getData(@Context HttpServletRequest request, @QueryParam("preparedId") String preparedId,
-                            @QueryParam("sessionId") String sessionId, @QueryParam("investigationIds") String investigationIds,
+    public Response getData(@Context HttpServletRequest request, @QueryParam(RequestIdNames.preparedId) String preparedId,
+                            @QueryParam(RequestIdNames.sessionId) String sessionId, @QueryParam("investigationIds") String investigationIds,
                             @QueryParam("datasetIds") String datasetIds, @QueryParam("datafileIds") String datafileIds,
                             @QueryParam("compress") boolean compress, @QueryParam("zip") boolean zip,
                             @QueryParam("outname") String outname, @HeaderParam("Range") String range) throws BadRequestException,
-            NotFoundException, InternalException, InsufficientPrivilegesException, DataNotOnlineException {
-        Response response = null;
+            NotFoundException, InternalException, InsufficientPrivilegesException, DataNotOnlineException, NotImplementedException {
 
-        long offset = 0;
-        if (range != null) {
-
-            Matcher m = rangeRe.matcher(range);
-            if (!m.matches()) {
-                throw new BadRequestException("The range must match " + rangeRe.pattern());
-            }
-            offset = Long.parseLong(m.group(1));
-            logger.debug("Range " + range + " -> offset " + offset);
-        }
-
-        if (preparedId != null) {
-            response = idsBean.getData(preparedId, outname, offset, request.getRemoteAddr());
-        } else {
-            response = idsBean.getData(sessionId, investigationIds, datasetIds, datafileIds, compress, zip, outname,
-                    offset, request.getRemoteAddr());
-        }
-        return response;
+        var handler = new GetDataHandler(request.getRemoteAddr(), preparedId, sessionId, investigationIds, datasetIds, datafileIds, compress, zip,  outname, range);
+        return handler.handle().getResponse();
     }
 
     /**
@@ -209,21 +291,20 @@ public Response getData(@Context HttpServletRequest request, @QueryParam("prepar
      * @throws InternalException
      * @throws NotFoundException
      * @throws InsufficientPrivilegesException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("getDatafileIds")
     @Produces(MediaType.APPLICATION_JSON)
-    public String getDatafileIds(@Context HttpServletRequest request, @QueryParam("preparedId") String preparedId,
-                                 @QueryParam("sessionId") String sessionId, @QueryParam("investigationIds") String investigationIds,
+    public String getDatafileIds(@Context HttpServletRequest request, @QueryParam(RequestIdNames.preparedId) String preparedId,
+                                 @QueryParam(RequestIdNames.sessionId) String sessionId, @QueryParam("investigationIds") String investigationIds,
                                  @QueryParam("datasetIds") String datasetIds, @QueryParam("datafileIds") String datafileIds)
-            throws BadRequestException, InternalException, NotFoundException, InsufficientPrivilegesException {
-        if (preparedId != null) {
-            return idsBean.getDatafileIds(preparedId, request.getRemoteAddr());
-        } else {
-            return idsBean.getDatafileIds(sessionId, investigationIds, datasetIds, datafileIds,
-                    request.getRemoteAddr());
-        }
+            throws BadRequestException, InternalException, NotFoundException, InsufficientPrivilegesException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new GetDataFileIdsHandler(request.getRemoteAddr(), preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+        return handler.handle().getString();
     }
 
     /**
@@ -232,13 +313,21 @@ public String getDatafileIds(@Context HttpServletRequest request, @QueryParam("p
      * obtained.
      *
      * @return the url of the icat server
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
+     * @throws NotFoundException 
+     * @throws InsufficientPrivilegesException 
+     * @throws BadRequestException 
+     * @throws InternalException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("getIcatUrl")
     @Produces(MediaType.TEXT_PLAIN)
-    public String getIcatUrl(@Context HttpServletRequest request) {
-        return idsBean.getIcatUrl(request.getRemoteAddr());
+    public String getIcatUrl(@Context HttpServletRequest request) throws InternalException, BadRequestException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new GetIcatUrlHandler(request.getRemoteAddr());
+        return handler.handle().getString();
     }
 
     /**
@@ -251,14 +340,20 @@ public String getIcatUrl(@Context HttpServletRequest request) {
      * @return a json string.
      * @throws InternalException
      * @throws InsufficientPrivilegesException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
+     * @throws NotFoundException 
+     * @throws BadRequestException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("getServiceStatus")
     @Produces(MediaType.APPLICATION_JSON)
-    public String getServiceStatus(@Context HttpServletRequest request, @QueryParam("sessionId") String sessionId)
-            throws InternalException, InsufficientPrivilegesException {
-        return idsBean.getServiceStatus(sessionId, request.getRemoteAddr());
+    public String getServiceStatus(@Context HttpServletRequest request, @QueryParam(RequestIdNames.sessionId) String sessionId)
+            throws InternalException, InsufficientPrivilegesException, BadRequestException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new GetServiceStatusHandler(request.getRemoteAddr(), sessionId);
+        return handler.handle().getString();
     }
 
     /**
@@ -277,20 +372,34 @@ public String getServiceStatus(@Context HttpServletRequest request, @QueryParam(
      * @throws NotFoundException
      * @throws InsufficientPrivilegesException
      * @throws InternalException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("getSize")
     @Produces(MediaType.TEXT_PLAIN)
-    public long getSize(@Context HttpServletRequest request, @QueryParam("preparedId") String preparedId,
-                        @QueryParam("sessionId") String sessionId, @QueryParam("investigationIds") String investigationIds,
+    public long getSize(@Context HttpServletRequest request, @QueryParam(RequestIdNames.preparedId) String preparedId,
+                        @QueryParam(RequestIdNames.sessionId) String sessionId, @QueryParam("investigationIds") String investigationIds,
                         @QueryParam("datasetIds") String datasetIds, @QueryParam("datafileIds") String datafileIds)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-        if (preparedId != null) {
-            return idsBean.getSize(preparedId, request.getRemoteAddr());
-        } else {
-            return idsBean.getSize(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
+            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException, DataNotOnlineException, NotImplementedException {
+
+
+        var result = ValueContainer.getInvalid();
+
+        // trying fast computation
+        if(sessionId != null) {
+            var fastHandler = new GetSizeHandlerForFastProcessing(request.getRemoteAddr(), sessionId, investigationIds, datasetIds, datafileIds);
+            result = fastHandler.handle();
         }
+
+        // otherwise normal computation
+        if(result.isInvalid()) {
+            var handler = new GetSizeHandler(request.getRemoteAddr(), preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+            result = handler.handle();
+        }
+
+        return result.getLong();
     }
 
     /**
@@ -315,29 +424,32 @@ public long getSize(@Context HttpServletRequest request, @QueryParam("preparedId
      * @throws NotFoundException
      * @throws InsufficientPrivilegesException
      * @throws InternalException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("getStatus")
     @Produces(MediaType.TEXT_PLAIN)
-    public String getStatus(@Context HttpServletRequest request, @QueryParam("preparedId") String preparedId,
-                            @QueryParam("sessionId") String sessionId, @QueryParam("investigationIds") String investigationIds,
+    public String getStatus(@Context HttpServletRequest request, @QueryParam(RequestIdNames.preparedId) String preparedId,
+                            @QueryParam(RequestIdNames.sessionId) String sessionId, @QueryParam("investigationIds") String investigationIds,
                             @QueryParam("datasetIds") String datasetIds, @QueryParam("datafileIds") String datafileIds)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
-        if (preparedId != null) {
-            return idsBean.getStatus(preparedId, request.getRemoteAddr());
-        } else {
-            return idsBean.getStatus(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
+            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException, DataNotOnlineException, NotImplementedException {
+
+        // special case for getStatus request: getting status is possible without authentification
+        if (sessionId == null && preparedId == null) {
+            try {
+                sessionId = ServiceProvider.getInstance().getIcatReader().getSessionId();
+            } catch (IcatException_Exception e) {
+                throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
+            }
         }
-    }
 
-    @PostConstruct
-    private void init() {
-        logger.info("creating IdsService");
-        rangeRe = Pattern.compile("bytes=(\\d+)-");
-        logger.info("created IdsService");
+        var handler = new GetStatusHandler(request.getRemoteAddr(), preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+        return handler.handle().getString();
     }
 
+
     /**
      * Returns true if all the data files are ready to be downloaded. As a side
      * effect, if any data files are archived and no restoration has been
@@ -355,29 +467,42 @@ private void init() {
      * @throws BadRequestException
      * @throws NotFoundException
      * @throws InternalException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
+     * @throws InsufficientPrivilegesException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("isPrepared")
     @Produces(MediaType.TEXT_PLAIN)
-    public boolean isPrepared(@Context HttpServletRequest request, @QueryParam("preparedId") String preparedId)
-            throws BadRequestException, NotFoundException, InternalException {
-        return idsBean.isPrepared(preparedId, request.getRemoteAddr());
+    public boolean isPrepared(@Context HttpServletRequest request, @QueryParam(RequestIdNames.preparedId) String preparedId)
+            throws BadRequestException, NotFoundException, InternalException, InsufficientPrivilegesException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new IsPreparedHandler(request.getRemoteAddr(), preparedId);
+        return handler.handle().getBool();
     }
 
     /**
-     * An ids server can be configured to be read only. This returns the
+     * An ids server can be configured to be read only. This returns thenew DfProcessQueue()
      * readOnly status of the server.
      *
      * @title isReadOnly
      * @return true if readonly, else false
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
+     * @throws NotFoundException 
+     * @throws InsufficientPrivilegesException 
+     * @throws BadRequestException 
+     * @throws InternalException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("isReadOnly")
     @Produces(MediaType.TEXT_PLAIN)
-    public boolean isReadOnly(@Context HttpServletRequest request) {
-        return idsBean.isReadOnly(request.getRemoteAddr());
+    public boolean isReadOnly(@Context HttpServletRequest request) throws InternalException, BadRequestException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new IsReadOnlyHandler(request.getRemoteAddr());
+        return handler.handle().getBool();
     }
 
     /**
@@ -386,13 +511,21 @@ public boolean isReadOnly(@Context HttpServletRequest request) {
      *
      * @title isTwoLevel
      * @return true if twoLevel, else false
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
+     * @throws NotFoundException 
+     * @throws InsufficientPrivilegesException 
+     * @throws BadRequestException 
+     * @throws InternalException 
      * @statuscode 200 To indicate success
      */
     @GET
     @Path("isTwoLevel")
     @Produces(MediaType.TEXT_PLAIN)
-    public boolean isTwoLevel(@Context HttpServletRequest request) {
-        return idsBean.isTwoLevel(request.getRemoteAddr());
+    public boolean isTwoLevel(@Context HttpServletRequest request) throws InternalException, BadRequestException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new IsTwoLevelHandler(request.getRemoteAddr());
+        return handler.handle().getBool();
     }
 
     /**
@@ -434,19 +567,22 @@ public String ping() {
      * @throws InsufficientPrivilegesException
      * @throws NotFoundException
      * @throws InternalException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @POST
     @Path("prepareData")
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
     @Produces(MediaType.TEXT_PLAIN)
-    public String prepareData(@Context HttpServletRequest request, @FormParam("sessionId") String sessionId,
+    public String prepareData(@Context HttpServletRequest request, @FormParam(RequestIdNames.sessionId) String sessionId,
                               @FormParam("investigationIds") String investigationIds, @FormParam("datasetIds") String datasetIds,
                               @FormParam("datafileIds") String datafileIds, @FormParam("compress") boolean compress,
                               @FormParam("zip") boolean zip)
-            throws BadRequestException, InsufficientPrivilegesException, NotFoundException, InternalException {
-        return idsBean.prepareData(sessionId, investigationIds, datasetIds, datafileIds, compress, zip,
-                request.getRemoteAddr());
+            throws BadRequestException, InsufficientPrivilegesException, NotFoundException, InternalException, NotImplementedException, DataNotOnlineException {
+
+        var handler = new PrepareDataHandler(request.getRemoteAddr(), sessionId, investigationIds, datasetIds, datafileIds, compress, zip);
+        return handler.handle().getString();
     }
 
     /**
@@ -478,14 +614,16 @@ public String prepareData(@Context HttpServletRequest request, @FormParam("sessi
     @Consumes(MediaType.APPLICATION_OCTET_STREAM)
     @Produces(MediaType.APPLICATION_JSON)
     public Response put(@Context HttpServletRequest request, InputStream body,
-                        @QueryParam("sessionId") String sessionId, @QueryParam("name") String name,
+                        @QueryParam(RequestIdNames.sessionId) String sessionId, @QueryParam("name") String name,
                         @QueryParam("datafileFormatId") String datafileFormatId, @QueryParam("datasetId") String datasetId,
                         @QueryParam("description") String description, @QueryParam("doi") String doi,
                         @QueryParam("datafileCreateTime") String datafileCreateTime,
                         @QueryParam("datafileModTime") String datafileModTime) throws BadRequestException, NotFoundException,
             InternalException, InsufficientPrivilegesException, NotImplementedException, DataNotOnlineException {
-        return idsBean.put(body, sessionId, name, datafileFormatId, datasetId, description, doi, datafileCreateTime,
-                datafileModTime, false, false, request.getRemoteAddr());
+
+        var handler = new PutHandler(request.getRemoteAddr(), sessionId, body, name, datafileFormatId, datasetId, 
+                                description, doi, datafileCreateTime, datafileModTime, false, false);
+        return handler.handle().getResponse();
     }
 
     /**
@@ -514,62 +652,63 @@ public Response put(@Context HttpServletRequest request, InputStream body,
     @Deprecated
     public Response putAsPost(@Context HttpServletRequest request) throws BadRequestException, NotFoundException,
             InternalException, InsufficientPrivilegesException, NotImplementedException, DataNotOnlineException {
-        try {
-            String sessionId = null;
-            String name = null;
-            String datafileFormatId = null;
-            String datasetId = null;
-            String description = null;
-            String doi = null;
-            String datafileCreateTime = null;
-            String datafileModTime = null;
-            Response result = null;
-            boolean wrap = false;
-            boolean padding = false;
-
-            // Parse the request
-            for (Part part : request.getParts()) {
-                String fieldName = part.getName();
-                InputStream stream = part.getInputStream();
-                if (part.getSubmittedFileName() == null) {
-                    String value = new String(stream.readAllBytes(), StandardCharsets.UTF_8);
-                    if (fieldName.equals("sessionId")) {
-                        sessionId = value;
-                    } else if (fieldName.equals("name")) {
-                        name = value;
-                    } else if (fieldName.equals("datafileFormatId")) {
-                        datafileFormatId = value;
-                    } else if (fieldName.equals("datasetId")) {
-                        datasetId = value;
-                    } else if (fieldName.equals("description")) {
-                        description = value;
-                    } else if (fieldName.equals("doi")) {
-                        doi = value;
-                    } else if (fieldName.equals("datafileCreateTime")) {
-                        datafileCreateTime = value;
-                    } else if (fieldName.equals("datafileModTime")) {
-                        datafileModTime = value;
-                    } else if (fieldName.equals("wrap")) {
-                        wrap = (value != null && value.toUpperCase().equals("TRUE"));
-                    } else if (fieldName.equals("padding")) {
-                        padding = (value != null && value.toUpperCase().equals("TRUE"));
-                    } else {
-                        throw new BadRequestException("Form field " + fieldName + "is not recognised");
-                    }
-                } else {
-                    if (name == null) {
-                        name = part.getSubmittedFileName();
+                try {
+                    String sessionId = null;
+                    String name = null;
+                    String datafileFormatId = null;
+                    String datasetId = null;
+                    String description = null;
+                    String doi = null;
+                    String datafileCreateTime = null;
+                    String datafileModTime = null;
+                    Response result = null;
+                    boolean wrap = false;
+                    boolean padding = false;
+        
+                    // Parse the request
+                    for (Part part : request.getParts()) {
+                        String fieldName = part.getName();
+                        InputStream stream = part.getInputStream();
+                        if (part.getSubmittedFileName() == null) {
+                            String value = new String(stream.readAllBytes(), StandardCharsets.UTF_8);
+                            if (fieldName.equals("sessionId")) {
+                                sessionId = value;
+                            } else if (fieldName.equals("name")) {
+                                name = value;
+                            } else if (fieldName.equals("datafileFormatId")) {
+                                datafileFormatId = value;
+                            } else if (fieldName.equals("datasetId")) {
+                                datasetId = value;
+                            } else if (fieldName.equals("description")) {
+                                description = value;
+                            } else if (fieldName.equals("doi")) {
+                                doi = value;
+                            } else if (fieldName.equals("datafileCreateTime")) {
+                                datafileCreateTime = value;
+                            } else if (fieldName.equals("datafileModTime")) {
+                                datafileModTime = value;
+                            } else if (fieldName.equals("wrap")) {
+                                wrap = (value != null && value.toUpperCase().equals("TRUE"));
+                            } else if (fieldName.equals("padding")) {
+                                padding = (value != null && value.toUpperCase().equals("TRUE"));
+                            } else {
+                                throw new BadRequestException("Form field " + fieldName + "is not recognised");
+                            }
+                        } else {
+                            if (name == null) {
+                                name = part.getSubmittedFileName();
+                            }
+                            var handler = new PutHandler(request.getRemoteAddr(), sessionId, stream, name, datafileFormatId, datasetId, description, 
+                                            doi, datafileCreateTime, datafileModTime, wrap, padding);
+                            result = handler.handle().getResponse();
+                        }
                     }
-                    result = idsBean.put(stream, sessionId, name, datafileFormatId, datasetId, description, doi,
-                            datafileCreateTime, datafileModTime, wrap, padding, request.getRemoteAddr());
+                    return result;
+                } catch (IOException e) {
+                    throw new InternalException(e.getClass() + " " + e.getMessage());
+                } catch (ServletException e) {
+                    throw new BadRequestException("Multipart content expected");
                 }
-            }
-            return result;
-        } catch (IOException e) {
-            throw new InternalException(e.getClass() + " " + e.getMessage());
-        } catch (ServletException e) {
-            throw new BadRequestException("Multipart content expected");
-        }
     }
 
     /**
@@ -594,19 +733,19 @@ public Response putAsPost(@Context HttpServletRequest request) throws BadRequest
      * @throws NotFoundException
      * @throws InternalException
      * @throws InsufficientPrivilegesException
+     * @throws NotImplementedException 
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @POST
     @Path("reset")
-    public void reset(@Context HttpServletRequest request, @FormParam("preparedId") String preparedId,
-                      @FormParam("sessionId") String sessionId, @FormParam("investigationIds") String investigationIds,
+    public void reset(@Context HttpServletRequest request, @FormParam(RequestIdNames.preparedId) String preparedId,
+                      @FormParam(RequestIdNames.sessionId) String sessionId, @FormParam("investigationIds") String investigationIds,
                       @FormParam("datasetIds") String datasetIds, @FormParam("datafileIds") String datafileIds)
-            throws BadRequestException, InternalException, NotFoundException, InsufficientPrivilegesException {
-        if (preparedId != null) {
-            idsBean.reset(preparedId, request.getRemoteAddr());
-        } else {
-            idsBean.reset(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
-        }
+            throws BadRequestException, InternalException, NotFoundException, InsufficientPrivilegesException, DataNotOnlineException, NotImplementedException {
+
+        var handler = new ResetHandler(request.getRemoteAddr(), preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+        handler.handle();
 
     }
 
@@ -626,17 +765,20 @@ public void reset(@Context HttpServletRequest request, @FormParam("preparedId")
      * @throws InsufficientPrivilegesException
      * @throws InternalException
      * @throws NotFoundException
+     * @throws DataNotOnlineException 
      * @statuscode 200 To indicate success
      */
     @POST
     @Path("restore")
     @Consumes("application/x-www-form-urlencoded")
-    public void restore(@Context HttpServletRequest request, @FormParam("sessionId") String sessionId,
+    public void restore(@Context HttpServletRequest request, @FormParam(RequestIdNames.sessionId) String sessionId,
                         @FormParam("investigationIds") String investigationIds, @FormParam("datasetIds") String datasetIds,
                         @FormParam("datafileIds") String datafileIds)
             throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
-            NotFoundException {
-        idsBean.restore(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
+            NotFoundException, DataNotOnlineException {
+
+        var handler = new RestoreHandler(request.getRemoteAddr(), sessionId, investigationIds, datasetIds, datafileIds);
+        handler.handle();
     }
 
 
@@ -662,11 +804,13 @@ public void restore(@Context HttpServletRequest request, @FormParam("sessionId")
     @POST
     @Path("write")
     @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
-    public void write(@Context HttpServletRequest request, @FormParam("sessionId") String sessionId,
+    public void write(@Context HttpServletRequest request, @FormParam(RequestIdNames.sessionId) String sessionId,
                       @FormParam("investigationIds") String investigationIds, @FormParam("datasetIds") String datasetIds,
                       @FormParam("datafileIds") String datafileIds)
             throws NotImplementedException, BadRequestException, InsufficientPrivilegesException, InternalException,
             NotFoundException, DataNotOnlineException {
-        idsBean.write(sessionId, investigationIds, datasetIds, datafileIds, request.getRemoteAddr());
+
+        var handler = new WriteHandler(request.getRemoteAddr(), sessionId, investigationIds, datasetIds, datafileIds);
+        handler.handle();
     }
 }
diff --git a/src/main/java/org/icatproject/ids/Prepared.java b/src/main/java/org/icatproject/ids/Prepared.java
deleted file mode 100644
index 886402c4..00000000
--- a/src/main/java/org/icatproject/ids/Prepared.java
+++ /dev/null
@@ -1,16 +0,0 @@
-package org.icatproject.ids;
-
-import java.util.Set;
-import java.util.SortedMap;
-import java.util.SortedSet;
-
-import org.icatproject.ids.plugin.DsInfo;
-
-/* This is a POJO with only package access so don't make data private */
-class Prepared {
-    boolean zip;
-    boolean compress;
-    SortedSet<DfInfoImpl> dfInfos;
-    SortedMap<Long, DsInfo> dsInfos;
-    Set<Long> emptyDatasets;
-}
diff --git a/src/main/java/org/icatproject/ids/StorageUnit.java b/src/main/java/org/icatproject/ids/StorageUnit.java
deleted file mode 100644
index 9e4712fb..00000000
--- a/src/main/java/org/icatproject/ids/StorageUnit.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package org.icatproject.ids;
-
-enum StorageUnit {
-    DATASET, DATAFILE
-}
diff --git a/src/main/java/org/icatproject/ids/Tidier.java b/src/main/java/org/icatproject/ids/Tidier.java
index 7f1bd626..9d647de0 100644
--- a/src/main/java/org/icatproject/ids/Tidier.java
+++ b/src/main/java/org/icatproject/ids/Tidier.java
@@ -24,11 +24,20 @@
 import org.icatproject.Datafile;
 import org.icatproject.Dataset;
 import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.StorageUnit;
 import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
 import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.helpers.LocationHelper;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DatasetInfo;
 import org.icatproject.ids.plugin.DfInfo;
 import org.icatproject.ids.plugin.DsInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+import org.icatproject.ids.services.PropertyHandler;
 
 @Singleton
 @Startup
@@ -71,7 +80,7 @@ public void run() {
                                     List<Object> os = reader.search(query);
                                     logger.debug(query + " returns " + os.size() + " datasets");
                                     for (Object o : os) {
-                                        DsInfoImpl dsInfoImpl = new DsInfoImpl((Dataset) o);
+                                        DatasetInfo dsInfoImpl = new DatasetInfo((Dataset) o);
                                         logger.debug(
                                                 "Requesting archive of " + dsInfoImpl + " to recover main storage");
                                         fsm.queue(dsInfoImpl, DeferredOp.ARCHIVE);
@@ -123,9 +132,9 @@ public void run() {
                                     logger.debug(query + " returns " + os.size() + " datafiles");
                                     for (Object o : os) {
                                         Datafile df = (Datafile) o;
-                                        DfInfoImpl dfInfoImpl = new DfInfoImpl(df.getId(), df.getName(),
+                                        DatafileInfo dfInfoImpl = new DatafileInfo(df.getId(), df.getName(),
 
-                                                IdsBean.getLocation(df.getId(), df.getLocation()), df.getCreateId(),
+                                                LocationHelper.getLocation(df.getId(), df.getLocation()), df.getCreateId(),
                                                 df.getModId(), df.getDataset().getId());
 
 
@@ -206,8 +215,7 @@ static void cleanPreparedDir(Path preparedDir, int preparedCount) throws IOExcep
         }
     }
 
-    @EJB
-    private FiniteStateMachine fsm;
+    private FiniteStateMachine fsm = null;
 
     private MainStorageInterface mainStorage;
 
@@ -216,6 +224,9 @@ static void cleanPreparedDir(Path preparedDir, int preparedCount) throws IOExcep
     @EJB
     IcatReader reader;
 
+    @EJB
+    private LockManager lockManager;
+
     private long sizeCheckIntervalMillis;
     private long startArchivingLevel;
     private long stopArchivingLevel;
@@ -238,7 +249,12 @@ public void exit() {
     @PostConstruct
     public void init() {
         try {
+
             PropertyHandler propertyHandler = PropertyHandler.getInstance();
+            FiniteStateMachine.createInstance(reader, lockManager, propertyHandler.getStorageUnit());
+            this.fsm = FiniteStateMachine.getInstance();
+            this.fsm.init(); //if not yet initialized by IdsService do it now
+            
             sizeCheckIntervalMillis = propertyHandler.getSizeCheckIntervalMillis();
             preparedCount = propertyHandler.getPreparedCount();
             preparedDir = propertyHandler.getCacheDir().resolve("prepared");
diff --git a/src/main/java/org/icatproject/ids/enums/CallType.java b/src/main/java/org/icatproject/ids/enums/CallType.java
new file mode 100644
index 00000000..835e9956
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/enums/CallType.java
@@ -0,0 +1,5 @@
+package org.icatproject.ids.enums;
+
+public enum CallType {
+    INFO, PREPARE, READ, WRITE, MIGRATE
+}
diff --git a/src/main/java/org/icatproject/ids/DeferredOp.java b/src/main/java/org/icatproject/ids/enums/DeferredOp.java
similarity index 88%
rename from src/main/java/org/icatproject/ids/DeferredOp.java
rename to src/main/java/org/icatproject/ids/enums/DeferredOp.java
index 31ea7908..3cda8707 100644
--- a/src/main/java/org/icatproject/ids/DeferredOp.java
+++ b/src/main/java/org/icatproject/ids/enums/DeferredOp.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.enums;
 
 /*
  * Represents the type of action that was requested by a user.
diff --git a/src/main/java/org/icatproject/ids/enums/RequestIdNames.java b/src/main/java/org/icatproject/ids/enums/RequestIdNames.java
new file mode 100644
index 00000000..8bfdb689
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/enums/RequestIdNames.java
@@ -0,0 +1,7 @@
+package org.icatproject.ids.enums;
+
+public class RequestIdNames {
+    public static final String sessionId = "sessionId";
+    public static final String preparedId = "preparedId";
+
+}
diff --git a/src/main/java/org/icatproject/ids/enums/RequestType.java b/src/main/java/org/icatproject/ids/enums/RequestType.java
new file mode 100644
index 00000000..a79f83e5
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/enums/RequestType.java
@@ -0,0 +1,23 @@
+package org.icatproject.ids.enums;
+
+/**
+ * This enum contains all defined types of requests to this server
+ */
+public enum RequestType {
+    GETDATA, 
+    ARCHIVE, 
+    GETICATURL, 
+    GETDATAFILEIDS, 
+    GETSERVICESTATUS, 
+    GETSIZE, 
+    GETSTATUS, 
+    ISPREPARED, 
+    ISREADONLY, 
+    ISTWOLEVEL, 
+    PREPAREDATA, 
+    PUT,
+    RESET,
+    RESTORE,
+    WRITE,
+    DELETE
+}
diff --git a/src/main/java/org/icatproject/ids/Status.java b/src/main/java/org/icatproject/ids/enums/Status.java
similarity index 85%
rename from src/main/java/org/icatproject/ids/Status.java
rename to src/main/java/org/icatproject/ids/enums/Status.java
index 18c36540..abc187aa 100644
--- a/src/main/java/org/icatproject/ids/Status.java
+++ b/src/main/java/org/icatproject/ids/enums/Status.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.enums;
 
 /*
  *  These are the values that the getStatus methods can return.
diff --git a/src/main/java/org/icatproject/ids/enums/StorageUnit.java b/src/main/java/org/icatproject/ids/enums/StorageUnit.java
new file mode 100644
index 00000000..bd5779a3
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/enums/StorageUnit.java
@@ -0,0 +1,5 @@
+package org.icatproject.ids.enums;
+
+public enum StorageUnit {
+    DATASET, DATAFILE
+}
diff --git a/src/main/java/org/icatproject/ids/enums/ValueContainerType.java b/src/main/java/org/icatproject/ids/enums/ValueContainerType.java
new file mode 100644
index 00000000..cf7501ac
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/enums/ValueContainerType.java
@@ -0,0 +1,8 @@
+package org.icatproject.ids.enums;
+
+/**
+ * This enum provides all possible values of a ValueContainer
+ */
+public enum ValueContainerType {
+    INVALID, VOID, INT, LONG, BOOL, STRING, RESPONSE, INPUTSTREAM
+}
diff --git a/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachine.java b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachine.java
new file mode 100644
index 00000000..f115c8da
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachine.java
@@ -0,0 +1,225 @@
+package org.icatproject.ids.finiteStateMachine;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.Timer;
+import java.util.concurrent.ConcurrentHashMap;
+
+import jakarta.json.Json;
+import jakarta.json.stream.JsonGenerator;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.StorageUnit;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.LockInfo;
+
+public abstract class FiniteStateMachine {
+
+
+    private static FiniteStateMachine instance;
+
+    private static Boolean inited = false;
+
+    protected FiniteStateMachine(IcatReader reader, LockManager lockManager) {
+        this.reader = reader;
+        this.lockManager = lockManager;
+    }
+
+    public static void createInstance(IcatReader reader, LockManager lockManager, StorageUnit storageUnit) {
+
+        if(instance == null) {
+            if(storageUnit == StorageUnit.DATAFILE)
+                instance = new FiniteStateMachineForStorageUnitDatafile(reader, lockManager);
+            else if(storageUnit == StorageUnit.DATASET)
+                instance = new FiniteStateMachineForStorageUnitDataset(reader, lockManager);
+            else
+                instance = new FiniteStateMachineForSingleLevelStorage(reader, lockManager);
+        }
+    }
+
+    public static FiniteStateMachine getInstance() {
+        if(instance != null) {
+            return instance;
+        }
+
+        // If this assert was executed: Instance of FiniteStateMachine is not created. At First createInstance() has to be called at least once.
+        throw new RuntimeException("Instance of FiniteStateMachine is not created. At First createInstance() has to be called at least once.");
+    }
+
+    public abstract void queue(DataInfoBase dataInfo, DeferredOp deferredOp) throws InternalException;
+    protected abstract void scheduleTimer();
+    protected abstract void addDataInfoJson(JsonGenerator gen);
+
+    public enum RequestedState {
+        ARCHIVE_REQUESTED, DELETE_REQUESTED, RESTORE_REQUESTED, WRITE_REQUESTED, WRITE_THEN_ARCHIVE_REQUESTED
+    }
+
+    protected static Logger logger = LoggerFactory.getLogger(FiniteStateMachine.class);
+
+    /*
+     * Note that the veriable processOpsDelayMillis is used to either delay all deferred
+     * datafile operations or to delay dataset writes, depending on the setting of storageUnit.
+     */
+    protected long processOpsDelayMillis;
+
+    protected Map<DataInfoBase, RequestedState> deferredOpsQueue = new HashMap<>();
+
+    protected Map<DataInfoBase, RequestedState> dataInfoChanging = new HashMap<>();
+
+    protected Path markerDir;
+    protected long processQueueIntervalMillis;
+
+    protected PropertyHandler propertyHandler;
+
+    protected IcatReader reader;
+
+    protected LockManager lockManager;
+
+    protected Timer timer = new Timer("FSM Timer");
+
+    protected Long processOpsTime;
+
+    protected Set<Long> failures = ConcurrentHashMap.newKeySet();
+
+    public void exit() {
+        timer.cancel();
+        logger.info("Cancelled timer");
+    }
+
+    /**
+     * Find any DataFileInfo which may be offline
+     */
+    public Set<DataInfoBase> getMaybeOffline() {
+        Map<DataInfoBase, RequestedState> union;
+        synchronized (deferredOpsQueue) {
+            union = new HashMap<>(dataInfoChanging);
+            union.putAll(deferredOpsQueue);
+        }
+        Set<DataInfoBase> result = new HashSet<>();
+        for (Entry<DataInfoBase, RequestedState> entry : union.entrySet()) {
+            if (entry.getValue() != RequestedState.WRITE_REQUESTED) {
+                result.add(entry.getKey());
+            }
+        }
+        return result;
+    }
+
+    /**
+     * Find any DataFileInfo which are being restored or are queued for restoration
+     */
+    public Set<DataInfoBase> getRestoring() {
+        Map<DataInfoBase, RequestedState> union;
+        synchronized (deferredOpsQueue) {
+            union = new HashMap<>(dataInfoChanging);
+            union.putAll(deferredOpsQueue);
+        }
+        Set<DataInfoBase> result = new HashSet<>();
+        for (Entry<DataInfoBase, RequestedState> entry : union.entrySet()) {
+            if (entry.getValue() == RequestedState.RESTORE_REQUESTED) {
+                result.add(entry.getKey());
+            }
+        }
+        return result;
+    }
+
+    protected void addDataInfoJsonFromDeferredOpsQueue(JsonGenerator gen) {
+        Map<DataInfoBase, RequestedState> union;
+        synchronized (deferredOpsQueue) {
+            union = new HashMap<>(dataInfoChanging);
+            union.putAll(deferredOpsQueue);
+        }
+        gen.writeStartArray("opsQueue");
+        for (Entry<DataInfoBase, RequestedState> entry : union.entrySet()) {
+            DataInfoBase item = entry.getKey();
+            gen.writeStartObject().write("data", item.toString()).write("request", entry.getValue().name())
+                    .writeEnd();
+        }
+        gen.writeEnd(); // end Array("opsQueue")
+    }
+
+    public String getServiceStatus() throws InternalException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
+            
+            this.addDataInfoJson(gen);
+
+            Collection<LockInfo> lockInfo = lockManager.getLockInfo();
+            gen.write("lockCount", lockInfo.size());
+            gen.writeStartArray("locks");
+            for (LockInfo li : lockInfo) {
+                gen.writeStartObject().write("id", li.id).write("type", li.type.name()).write("count", li.count).writeEnd();
+            }
+            gen.writeEnd(); // end Array("locks")
+
+            gen.writeStartArray("failures");
+            for (Long failure : failures) {
+                gen.write(failure);
+            }
+            gen.writeEnd(); // end Array("failures")
+
+            gen.writeEnd(); // end Object()
+        }
+        return baos.toString();
+    }
+
+
+    public void init() {
+
+        try {
+            synchronized (inited) {
+                if(!inited) {
+                    propertyHandler = PropertyHandler.getInstance();
+                    processQueueIntervalMillis = propertyHandler.getProcessQueueIntervalSeconds() * 1000L;
+
+                    this.scheduleTimer();
+                        
+                    markerDir = propertyHandler.getCacheDir().resolve("marker");
+                    Files.createDirectories(markerDir);
+                    inited = true;
+                }
+            }
+        } catch (IOException e) {
+            throw new RuntimeException("FiniteStateMachine reports " + e.getClass() + " " + e.getMessage());
+        }
+
+    }
+
+    public void removeFromChanging(DataInfoBase dfInfo) {
+        synchronized (deferredOpsQueue) {
+            dataInfoChanging.remove(dfInfo);
+        }
+    }
+
+    public void recordSuccess(Long id) {
+        if (failures.remove(id)) {
+            logger.debug("Marking {} OK", id);
+        }
+    }
+
+    public void recordFailure(Long id) {
+        if (failures.add(id)) {
+            logger.debug("Marking {} as failure", id);
+        }
+    }
+
+    public void checkFailure(Long id) throws InternalException {
+        if (failures.contains(id)) {
+            throw new InternalException("Restore failed");
+        }
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForSingleLevelStorage.java b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForSingleLevelStorage.java
new file mode 100644
index 00000000..7ffb349d
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForSingleLevelStorage.java
@@ -0,0 +1,35 @@
+package org.icatproject.ids.finiteStateMachine;
+
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class FiniteStateMachineForSingleLevelStorage extends FiniteStateMachine {
+
+    protected FiniteStateMachineForSingleLevelStorage(IcatReader reader, LockManager lockManager) {
+        super(reader, lockManager);
+    }
+
+
+    @Override
+    public void queue(DataInfoBase dataInfo, DeferredOp deferredOp) throws InternalException {
+        throw new InternalException("### Operation is not permitted for single level storage");
+    }
+
+
+    @Override
+    protected void scheduleTimer() {
+        //nothing to do here for single level storage
+    }
+
+
+    @Override
+    protected void addDataInfoJson(JsonGenerator gen) {
+        gen.writeStartArray("opsQueue").writeEnd();
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForStorageUnitDatafile.java b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForStorageUnitDatafile.java
new file mode 100644
index 00000000..88543bb1
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForStorageUnitDatafile.java
@@ -0,0 +1,277 @@
+package org.icatproject.ids.finiteStateMachine;
+
+import java.io.IOException;
+import java.nio.file.FileAlreadyExistsException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import java.util.TimerTask;
+
+import org.icatproject.Dataset;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.plugin.AlreadyLockedException;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.icatproject.ids.services.LockManager.LockType;
+import org.icatproject.ids.thread.DfArchiver;
+import org.icatproject.ids.thread.DfDeleter;
+import org.icatproject.ids.thread.DfRestorer;
+import org.icatproject.ids.thread.DfWriter;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class FiniteStateMachineForStorageUnitDatafile extends FiniteStateMachine {
+
+    protected FiniteStateMachineForStorageUnitDatafile(IcatReader icatReader, LockManager lockManager) {
+        super(icatReader, lockManager);
+    }
+
+
+    @Override
+    protected void scheduleTimer() {
+        processOpsDelayMillis = propertyHandler.getDelayDatafileOperations() * 1000L;
+        timer.schedule(new DfProcessQueue(), processQueueIntervalMillis);
+        logger.info("DfProcessQueue scheduled to run in " + processQueueIntervalMillis + " milliseconds");
+    }
+
+
+    @Override
+    protected void addDataInfoJson(JsonGenerator gen) {
+        this.addDataInfoJsonFromDeferredOpsQueue(gen);
+    }
+
+
+    public void queue(DataInfoBase dataInfo, DeferredOp deferredOp) throws InternalException {
+
+        var dfInfo = (DatafileInfo) dataInfo;
+        if(dfInfo == null) throw new InternalException("DataInfoBase object could not be casted into a DataFileInfo. Did you handed over a DataSetInfo instead?");
+
+        logger.info("Requesting " + deferredOp + " of datafile " + dfInfo);
+
+        synchronized (deferredOpsQueue) {
+
+            if (processOpsTime == null) {
+                processOpsTime = System.currentTimeMillis() + processOpsDelayMillis;
+                final Date d = new Date(processOpsTime);
+                logger.debug("Requesting delay operations till " + d);
+            }
+
+            final RequestedState state = this.deferredOpsQueue.get(dfInfo);
+            if (state == null) {
+                if (deferredOp == DeferredOp.WRITE) {
+                    try {
+                        Path marker = markerDir.resolve(Long.toString(dfInfo.getId()));
+                        Files.createFile(marker);
+                        logger.debug("Created marker " + marker);
+                    } catch (FileAlreadyExistsException e) {
+                        // Pass will ignore this
+                    } catch (IOException e) {
+                        throw new InternalException(e.getClass() + " " + e.getMessage());
+                    }
+                    deferredOpsQueue.put(dfInfo, RequestedState.WRITE_REQUESTED);
+                } else if (deferredOp == DeferredOp.ARCHIVE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.ARCHIVE_REQUESTED);
+                } else if (deferredOp == DeferredOp.RESTORE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.RESTORE_REQUESTED);
+                } else if (deferredOp == DeferredOp.DELETE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.DELETE_REQUESTED);
+                }
+            } else if (state == RequestedState.ARCHIVE_REQUESTED) {
+                if (deferredOp == DeferredOp.RESTORE) {
+                    deferredOpsQueue.remove(dfInfo);
+                } else if (deferredOp == DeferredOp.DELETE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.DELETE_REQUESTED);
+                }
+            } else if (state == RequestedState.DELETE_REQUESTED) {
+                // No way out
+            } else if (state == RequestedState.RESTORE_REQUESTED) {
+                if (deferredOp == DeferredOp.DELETE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.DELETE_REQUESTED);
+                } else if (deferredOp == DeferredOp.ARCHIVE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.ARCHIVE_REQUESTED);
+                }
+            } else if (state == RequestedState.WRITE_REQUESTED) {
+                if (deferredOp == DeferredOp.DELETE) {
+                    deferredOpsQueue.remove(dfInfo);
+                } else if (deferredOp == DeferredOp.ARCHIVE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.WRITE_THEN_ARCHIVE_REQUESTED);
+                }
+            } else if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
+                if (deferredOp == DeferredOp.DELETE) {
+                    deferredOpsQueue.remove(dfInfo);
+                } else if (deferredOp == DeferredOp.RESTORE) {
+                    deferredOpsQueue.put(dfInfo, RequestedState.WRITE_REQUESTED);
+                }
+            }
+        }
+    }
+
+
+    private class DfProcessQueue extends TimerTask {
+
+        @Override
+        public void run() {
+            try {
+                synchronized (deferredOpsQueue) {
+                    if (processOpsTime != null && System.currentTimeMillis() > processOpsTime && !deferredOpsQueue.isEmpty()) {
+                        processOpsTime = null;
+                        logger.debug("deferredDfOpsQueue has " + deferredOpsQueue.size() + " entries");
+                        List<DatafileInfo> writes = new ArrayList<>();
+                        List<DatafileInfo> archives = new ArrayList<>();
+                        List<DatafileInfo> restores = new ArrayList<>();
+                        List<DatafileInfo> deletes = new ArrayList<>();
+                        Map<Long, Lock> writeLocks = new HashMap<>();
+                        Map<Long, Lock> archiveLocks = new HashMap<>();
+                        Map<Long, Lock> restoreLocks = new HashMap<>();
+                        Map<Long, Lock> deleteLocks = new HashMap<>();
+
+                        Map<DataInfoBase, RequestedState> newOps = new HashMap<>();
+                        final Iterator<Entry<DataInfoBase, RequestedState>> it = deferredOpsQueue.entrySet().iterator();
+                        while (it.hasNext()) {
+                            Entry<DataInfoBase, RequestedState> opEntry = it.next();
+                            var dfInfo = (DatafileInfo) opEntry.getKey();
+
+                            if(dfInfo == null) throw new RuntimeException("Could not cast DataInfoBase to DataFileInfo. Did you handed over another sub type?");
+
+                            Long dsId = dfInfo.getDsId();
+                            DatasetInfo dsInfo;
+                            try {
+                                Dataset ds = (Dataset) reader.get("Dataset ds INCLUDE ds.investigation.facility", dsId);
+                                dsInfo = new DatasetInfo(ds);
+                            } catch (Exception e) {
+                                logger.error("Could not get dsInfo {}: {}.", dsId, e.getMessage());
+                                continue;
+                            }
+                            if (!dataInfoChanging.containsKey(dfInfo)) {
+                                final RequestedState state = opEntry.getValue();
+                                logger.debug(dfInfo + " " + state);
+                                if (state == RequestedState.WRITE_REQUESTED) {
+                                    if (!writeLocks.containsKey(dsId)) {
+                                        try {
+                                            writeLocks.put(dsId, lockManager.lock(dsInfo, LockType.SHARED));
+                                        } catch (AlreadyLockedException e) {
+                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
+                                            continue;
+                                        } catch (IOException e) {
+                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
+                                            continue;
+                                        }
+                                    }
+                                    it.remove();
+                                    dataInfoChanging.put(dfInfo, state);
+                                    writes.add(dfInfo);
+                                } else if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
+                                    if (!writeLocks.containsKey(dsId)) {
+                                        try {
+                                            writeLocks.put(dsId, lockManager.lock(dsInfo, LockType.SHARED));
+                                        } catch (AlreadyLockedException e) {
+                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
+                                            continue;
+                                        } catch (IOException e) {
+                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
+                                            continue;
+                                        }
+                                    }
+                                    it.remove();
+                                    dataInfoChanging.put(dfInfo, RequestedState.WRITE_REQUESTED);
+                                    writes.add(dfInfo);
+                                    newOps.put(dfInfo, RequestedState.ARCHIVE_REQUESTED);
+                                } else if (state == RequestedState.ARCHIVE_REQUESTED) {
+                                    if (!archiveLocks.containsKey(dsId)) {
+                                        try {
+                                            archiveLocks.put(dsId, lockManager.lock(dsInfo, LockType.EXCLUSIVE));
+                                        } catch (AlreadyLockedException e) {
+                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
+                                            continue;
+                                        } catch (IOException e) {
+                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
+                                            continue;
+                                        }
+                                    }
+                                    it.remove();
+                                    dataInfoChanging.put(dfInfo, state);
+                                    archives.add(dfInfo);
+                                } else if (state == RequestedState.RESTORE_REQUESTED) {
+                                    if (!restoreLocks.containsKey(dsId)) {
+                                        try {
+                                            restoreLocks.put(dsId, lockManager.lock(dsInfo, LockType.EXCLUSIVE));
+                                        } catch (AlreadyLockedException e) {
+                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
+                                            continue;
+                                        } catch (IOException e) {
+                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
+                                            continue;
+                                        }
+                                    }
+                                    it.remove();
+                                    dataInfoChanging.put(dfInfo, state);
+                                    restores.add(dfInfo);
+                                } else if (state == RequestedState.DELETE_REQUESTED) {
+                                    if (!deleteLocks.containsKey(dsId)) {
+                                        try {
+                                            deleteLocks.put(dsId, lockManager.lock(dsInfo, LockType.EXCLUSIVE));
+                                        } catch (AlreadyLockedException e) {
+                                            logger.debug("Could not acquire lock on " + dsId + ", hold back " + state);
+                                            continue;
+                                        } catch (IOException e) {
+                                            logger.error("I/O exception " + e.getMessage() + " locking " + dsId);
+                                            continue;
+                                        }
+                                    }
+                                    it.remove();
+                                    dataInfoChanging.put(dfInfo, state);
+                                    deletes.add(dfInfo);
+                                } else {
+                                    throw new AssertionError("Impossible state");
+                                }
+                            }
+                        }
+                        if (!newOps.isEmpty()) {
+                            deferredOpsQueue.putAll(newOps);
+                            logger.debug("Adding {} operations to be scheduled next time round", newOps.size());
+                        }
+                        if (!deferredOpsQueue.isEmpty()) {
+                            processOpsTime = 0L;
+                        }
+                        if (!writes.isEmpty()) {
+                            logger.debug("Launch thread to process " + writes.size() + " writes");
+                            Thread w = new Thread(new DfWriter(writes, propertyHandler, FiniteStateMachineForStorageUnitDatafile.this, writeLocks.values()));
+                            w.start();
+                        }
+                        if (!archives.isEmpty()) {
+                            logger.debug("Launch thread to process " + archives.size() + " archives");
+                            Thread w = new Thread(new DfArchiver(archives, propertyHandler, FiniteStateMachineForStorageUnitDatafile.this, archiveLocks.values()));
+                            w.start();
+                        }
+                        if (!restores.isEmpty()) {
+                            logger.debug("Launch thread to process " + restores.size() + " restores");
+                            Thread w = new Thread(new DfRestorer(restores, propertyHandler, FiniteStateMachineForStorageUnitDatafile.this, restoreLocks.values()));
+                            w.start();
+                        }
+                        if (!deletes.isEmpty()) {
+                            logger.debug("Launch thread to process " + deletes.size() + " deletes");
+                            Thread w = new Thread(new DfDeleter(deletes, propertyHandler, FiniteStateMachineForStorageUnitDatafile.this, deleteLocks.values()));
+                            w.start();
+                        }
+                    }
+                }
+            } finally {
+                timer.schedule(new DfProcessQueue(), processQueueIntervalMillis);
+            }
+
+        }
+
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForStorageUnitDataset.java b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForStorageUnitDataset.java
new file mode 100644
index 00000000..cbe0a5cd
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/finiteStateMachine/FiniteStateMachineForStorageUnitDataset.java
@@ -0,0 +1,203 @@
+package org.icatproject.ids.finiteStateMachine;
+
+import java.io.IOException;
+import java.nio.file.FileAlreadyExistsException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.TimerTask;
+
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.plugin.AlreadyLockedException;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.icatproject.ids.services.LockManager.LockType;
+import org.icatproject.ids.thread.DsArchiver;
+import org.icatproject.ids.thread.DsRestorer;
+import org.icatproject.ids.thread.DsWriter;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class FiniteStateMachineForStorageUnitDataset extends FiniteStateMachine {
+
+    protected Map<DataInfoBase, Long> writeTimes = new HashMap<>();
+
+    protected FiniteStateMachineForStorageUnitDataset(IcatReader reader, LockManager lockManager) {
+        super(reader, lockManager);
+    }
+
+
+    @Override
+    protected void scheduleTimer() {
+        processOpsDelayMillis = propertyHandler.getDelayDatasetWrites() * 1000L;
+        timer.schedule(new DsProcessQueue(), processQueueIntervalMillis);
+        logger.info("DsProcessQueue scheduled to run in " + processQueueIntervalMillis + " milliseconds");
+    }
+
+    @Override
+    protected void addDataInfoJson(JsonGenerator gen) {
+        this.addDataInfoJsonFromDeferredOpsQueue(gen);
+    }
+
+
+    public void queue(DataInfoBase dataInfo, DeferredOp deferredOp) throws InternalException {
+
+
+        logger.info("Requesting " + deferredOp + " of dataset " + dataInfo);
+
+        synchronized (deferredOpsQueue) {
+
+            final RequestedState state = this.deferredOpsQueue.get(dataInfo);
+            if (state == null) {
+                if (deferredOp == DeferredOp.WRITE) {
+                    requestWrite(dataInfo);
+                } else if (deferredOp == DeferredOp.ARCHIVE) {
+                    deferredOpsQueue.put(dataInfo, RequestedState.ARCHIVE_REQUESTED);
+                } else if (deferredOp == DeferredOp.RESTORE) {
+                    deferredOpsQueue.put(dataInfo, RequestedState.RESTORE_REQUESTED);
+                }
+            } else if (state == RequestedState.ARCHIVE_REQUESTED) {
+                if (deferredOp == DeferredOp.WRITE) {
+                    requestWrite(dataInfo);
+                    deferredOpsQueue.put(dataInfo, RequestedState.WRITE_THEN_ARCHIVE_REQUESTED);
+                } else if (deferredOp == DeferredOp.RESTORE) {
+                    deferredOpsQueue.put(dataInfo, RequestedState.RESTORE_REQUESTED);
+                }
+            } else if (state == RequestedState.RESTORE_REQUESTED) {
+                if (deferredOp == DeferredOp.WRITE) {
+                    requestWrite(dataInfo);
+                } else if (deferredOp == DeferredOp.ARCHIVE) {
+                    deferredOpsQueue.put(dataInfo, RequestedState.ARCHIVE_REQUESTED);
+                }
+            } else if (state == RequestedState.WRITE_REQUESTED) {
+                if (deferredOp == DeferredOp.WRITE) {
+                    setDelay(dataInfo);
+                } else if (deferredOp == DeferredOp.ARCHIVE) {
+                    deferredOpsQueue.put(dataInfo, RequestedState.WRITE_THEN_ARCHIVE_REQUESTED);
+                }
+            } else if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
+                if (deferredOp == DeferredOp.WRITE) {
+                    setDelay(dataInfo);
+                } else if (deferredOp == DeferredOp.RESTORE) {
+                    deferredOpsQueue.put(dataInfo, RequestedState.WRITE_REQUESTED);
+                }
+            }
+        }
+
+    }
+
+
+    private void requestWrite(DataInfoBase dsInfo) throws InternalException {
+        try {
+            Path marker = markerDir.resolve(Long.toString(dsInfo.getId()));
+            Files.createFile(marker);
+            logger.debug("Created marker " + marker);
+        } catch (FileAlreadyExistsException e) {
+            // Pass will ignore this
+        } catch (IOException e) {
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+        deferredOpsQueue.put(dsInfo, RequestedState.WRITE_REQUESTED);
+        setDelay(dsInfo);
+    }
+
+
+    private void setDelay(DataInfoBase dsInfo) {
+        writeTimes.put(dsInfo, System.currentTimeMillis() + processOpsDelayMillis);
+        if (logger.isDebugEnabled()) {
+            final Date d = new Date(writeTimes.get(dsInfo));
+            logger.debug("Requesting delay of writing of dataset " + dsInfo + " till " + d);
+        }
+    }
+
+
+    private class DsProcessQueue extends TimerTask {
+
+        @Override
+        public void run() {
+            try {
+                synchronized (deferredOpsQueue) {
+                    final long now = System.currentTimeMillis();
+                    Map<DataInfoBase, RequestedState> newOps = new HashMap<>();
+                    final Iterator<Entry<DataInfoBase, RequestedState>> it = deferredOpsQueue.entrySet().iterator();
+                    while (it.hasNext()) {
+                        final Entry<DataInfoBase, RequestedState> opEntry = it.next();
+                        final var dsInfo = (DatasetInfo) opEntry.getKey();
+
+
+                        if(dsInfo == null) throw new RuntimeException("Could not cast DataInfoBase to DataSetInfo. Did you handed over another sub type?");
+
+                        if (!dataInfoChanging.containsKey(dsInfo)) {
+                            final RequestedState state = opEntry.getValue();
+                            if (state == RequestedState.WRITE_REQUESTED
+                                    || state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
+                                if (now > writeTimes.get(dsInfo)) {
+                                    try {
+                                        Lock lock = lockManager.lock(dsInfo, LockType.SHARED);
+                                        logger.debug("Will process " + dsInfo + " with " + state);
+                                        writeTimes.remove(dsInfo);
+                                        dataInfoChanging.put(dsInfo, RequestedState.WRITE_REQUESTED);
+                                        it.remove();
+                                        final Thread w = new Thread(
+                                                new DsWriter(dsInfo, propertyHandler, FiniteStateMachineForStorageUnitDataset.this, reader, lock));
+                                        w.start();
+                                        if (state == RequestedState.WRITE_THEN_ARCHIVE_REQUESTED) {
+                                            newOps.put(dsInfo, RequestedState.ARCHIVE_REQUESTED);
+                                        }
+                                    } catch (AlreadyLockedException e) {
+                                        logger.debug("Could not acquire lock on " + dsInfo + ", hold back process with " + state);
+                                    } catch (IOException e) {
+                                        logger.error("I/O exception " + e.getMessage() + " locking " + dsInfo);
+                                    }
+                                }
+                            } else if (state == RequestedState.ARCHIVE_REQUESTED) {
+                                try {
+                                    Lock lock = lockManager.lock(dsInfo, LockType.EXCLUSIVE);
+                                    it.remove();
+                                    logger.debug("Will process " + dsInfo + " with " + state);
+                                    dataInfoChanging.put(dsInfo, state);
+                                    final Thread w = new Thread(
+                                            new DsArchiver(dsInfo, propertyHandler, FiniteStateMachineForStorageUnitDataset.this, lock));
+                                    w.start();
+                                } catch (AlreadyLockedException e) {
+                                    logger.debug("Could not acquire lock on " + dsInfo + ", hold back process with " + state);
+                                } catch (IOException e) {
+                                    logger.error("I/O exception " + e.getMessage() + " locking " + dsInfo);
+                                }
+                            } else if (state == RequestedState.RESTORE_REQUESTED) {
+                                try {
+                                    Lock lock = lockManager.lock(dsInfo, LockType.EXCLUSIVE);
+                                    logger.debug("Will process " + dsInfo + " with " + state);
+                                    dataInfoChanging.put(dsInfo, state);
+                                    it.remove();
+                                    final Thread w = new Thread(
+                                            new DsRestorer(dsInfo, propertyHandler, FiniteStateMachineForStorageUnitDataset.this, reader, lock));
+                                    w.start();
+                                } catch (AlreadyLockedException e) {
+                                    logger.debug("Could not acquire lock on " + dsInfo + ", hold back process with " + state);
+                                } catch (IOException e) {
+                                    logger.error("I/O exception " + e.getMessage() + " locking " + dsInfo);
+                                }
+                            }
+                        }
+                    }
+                    deferredOpsQueue.putAll(newOps);
+                }
+
+            } finally {
+                timer.schedule(new DsProcessQueue(), processQueueIntervalMillis);
+            }
+
+        }
+
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/CORSResponseFilter.java b/src/main/java/org/icatproject/ids/helpers/CORSResponseFilter.java
similarity index 95%
rename from src/main/java/org/icatproject/ids/CORSResponseFilter.java
rename to src/main/java/org/icatproject/ids/helpers/CORSResponseFilter.java
index b2c84e62..8c813be8 100644
--- a/src/main/java/org/icatproject/ids/CORSResponseFilter.java
+++ b/src/main/java/org/icatproject/ids/helpers/CORSResponseFilter.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.helpers;
 
 import java.io.IOException;
 
diff --git a/src/main/java/org/icatproject/ids/CheckedWithSizeInputStream.java b/src/main/java/org/icatproject/ids/helpers/CheckedWithSizeInputStream.java
similarity index 95%
rename from src/main/java/org/icatproject/ids/CheckedWithSizeInputStream.java
rename to src/main/java/org/icatproject/ids/helpers/CheckedWithSizeInputStream.java
index 2c12c9c5..d3d409e4 100644
--- a/src/main/java/org/icatproject/ids/CheckedWithSizeInputStream.java
+++ b/src/main/java/org/icatproject/ids/helpers/CheckedWithSizeInputStream.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.helpers;
 
 import java.io.FilterInputStream;
 import java.io.IOException;
diff --git a/src/main/java/org/icatproject/ids/Constants.java b/src/main/java/org/icatproject/ids/helpers/Constants.java
similarity index 93%
rename from src/main/java/org/icatproject/ids/Constants.java
rename to src/main/java/org/icatproject/ids/helpers/Constants.java
index ea2061aa..bc7d4aaa 100644
--- a/src/main/java/org/icatproject/ids/Constants.java
+++ b/src/main/java/org/icatproject/ids/helpers/Constants.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.helpers;
 
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/main/java/org/icatproject/ids/helpers/LocationHelper.java b/src/main/java/org/icatproject/ids/helpers/LocationHelper.java
new file mode 100644
index 00000000..b3c1e8b5
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/helpers/LocationHelper.java
@@ -0,0 +1,44 @@
+package org.icatproject.ids.helpers;
+
+import java.security.NoSuchAlgorithmException;
+
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.utils.IcatSecurity;
+
+public class LocationHelper {
+
+    public static String getLocation(long dfid, String location)
+            throws InsufficientPrivilegesException, InternalException {
+        if (location == null) {
+            throw new InternalException("location is null");
+        }
+
+        var key = ServiceProvider.getInstance().getPropertyHandler().getKey();
+        if (key == null) {
+            return location;
+        } else {
+            return getLocationFromDigest(dfid, location, key);
+        }
+    }
+
+
+    public static String getLocationFromDigest(long id, String locationWithHash, String key)
+            throws InternalException, InsufficientPrivilegesException {
+        int i = locationWithHash.lastIndexOf(' ');
+        try {
+            String location = locationWithHash.substring(0, i);
+            String hash = locationWithHash.substring(i + 1);
+            if (!hash.equals(IcatSecurity.digest(id, location, key))) {
+                throw new InsufficientPrivilegesException(
+                        "Location \"" + locationWithHash + "\" does not contain a valid hash.");
+            }
+            return location;
+        } catch (IndexOutOfBoundsException e) {
+            throw new InsufficientPrivilegesException("Location \"" + locationWithHash + "\" does not contain hash.");
+        } catch (NoSuchAlgorithmException e) {
+            throw new InternalException(e.getMessage());
+        }
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/RangeOutputStream.java b/src/main/java/org/icatproject/ids/helpers/RangeOutputStream.java
similarity index 98%
rename from src/main/java/org/icatproject/ids/RangeOutputStream.java
rename to src/main/java/org/icatproject/ids/helpers/RangeOutputStream.java
index 076ecf96..ffaa34be 100644
--- a/src/main/java/org/icatproject/ids/RangeOutputStream.java
+++ b/src/main/java/org/icatproject/ids/helpers/RangeOutputStream.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.helpers;
 
 import java.io.FilterOutputStream;
 import java.io.IOException;
diff --git a/src/main/java/org/icatproject/ids/helpers/SO.java b/src/main/java/org/icatproject/ids/helpers/SO.java
new file mode 100644
index 00000000..58e1ee4a
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/helpers/SO.java
@@ -0,0 +1,131 @@
+package org.icatproject.ids.helpers;
+
+import java.io.BufferedOutputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Map;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipException;
+import java.util.zip.ZipOutputStream;
+
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import jakarta.json.Json;
+import jakarta.json.stream.JsonGenerator;
+import jakarta.ws.rs.core.StreamingOutput;
+
+public class SO implements StreamingOutput {
+
+    private long offset;
+    private boolean zip;
+    private Map<Long, DataInfoBase> dsInfos;
+    private Lock lock;
+    private boolean compress;
+    private Map<Long, DataInfoBase> dfInfos;
+    private String ip;
+    private long start;
+    private Long transferId;
+    private ServiceProvider serviceProvider;
+
+    private static final int BUFSIZ = 2048;
+    private final static Logger logger = LoggerFactory.getLogger(SO.class);
+
+    public SO(Map<Long, DataInfoBase> dsInfos, Map<Long, DataInfoBase> dfInfos, long offset, boolean zip, boolean compress,
+       Lock lock, Long transferId, String ip, long start, ServiceProvider serviceProvider) {
+        this.offset = offset;
+        this.zip = zip;
+        this.dsInfos = dsInfos;
+        this.dfInfos = dfInfos;
+        this.lock = lock;
+        this.compress = compress;
+        this.transferId = transferId;
+        this.ip = ip;
+        this.start = start;
+        this.serviceProvider = serviceProvider;
+    }
+
+    @Override
+    public void write(OutputStream output) throws IOException {
+
+        Object transfer = "??";
+        try {
+            if (offset != 0) { // Wrap the stream if needed
+                output = new RangeOutputStream(output, offset, null);
+            }
+            byte[] bytes = new byte[BUFSIZ];
+            if (zip) {
+                ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(output));
+                if (!compress) {
+                    zos.setLevel(0); // Otherwise use default compression
+                }
+
+                for ( DataInfoBase  dataInfo : dfInfos.values()) {
+                    var dfInfo = (DatafileInfo) dataInfo;
+                    logger.debug("Adding " + dfInfo + " to zip");
+                    transfer = dfInfo;
+                    DataInfoBase dsInfo = dsInfos.get(dfInfo.getDsId() );
+                    String entryName = this.serviceProvider.getPropertyHandler().getZipMapper().getFullEntryName((DatasetInfo)dsInfo, (DatafileInfo)dfInfo);
+                    InputStream stream = null;
+                    try {
+                        zos.putNextEntry(new ZipEntry(entryName));
+                        stream = this.serviceProvider.getMainStorage().get(dfInfo.getLocation(), dfInfo.getCreateId(), dfInfo.getModId());
+                        int length;
+                        while ((length = stream.read(bytes)) >= 0) {
+                            zos.write(bytes, 0, length);
+                        }
+                    } catch (ZipException e) {
+                        logger.debug("Skipped duplicate");
+                    }
+                    zos.closeEntry();
+                    if (stream != null) {
+                        stream.close();
+                    }
+                }
+                zos.close();
+            } else {
+                DatafileInfo dfInfo = (DatafileInfo) dfInfos.values().iterator().next();
+                transfer = dfInfo;
+                InputStream stream = this.serviceProvider.getMainStorage().get(dfInfo.getDfLocation(), dfInfo.getCreateId(),
+                        dfInfo.getModId());
+                int length;
+                while ((length = stream.read(bytes)) >= 0) {
+                    output.write(bytes, 0, length);
+                }
+                output.close();
+                stream.close();
+            }
+
+            if (transferId != null) {
+                ByteArrayOutputStream baos = new ByteArrayOutputStream();
+                try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
+                    gen.write("transferId", transferId);
+                    gen.writeEnd();
+                }
+                this.serviceProvider.getTransmitter().processMessage("getData", ip, baos.toString(), start);
+            }
+
+        } catch (IOException e) {
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
+                gen.write("transferId", transferId);
+                gen.write("exceptionClass", e.getClass().toString());
+                gen.write("exceptionMessage", e.getMessage());
+                gen.writeEnd();
+            }
+            this.serviceProvider.getTransmitter().processMessage("getData", ip, baos.toString(), start);
+            logger.error("Failed to stream " + transfer + " due to " + e.getMessage());
+            throw e;
+        } finally {
+            lock.release();
+        }
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/helpers/ValueContainer.java b/src/main/java/org/icatproject/ids/helpers/ValueContainer.java
new file mode 100644
index 00000000..bb99efba
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/helpers/ValueContainer.java
@@ -0,0 +1,189 @@
+package org.icatproject.ids.helpers;
+
+import java.io.InputStream;
+
+import org.icatproject.ids.enums.ValueContainerType;
+import org.icatproject.ids.exceptions.InternalException;
+
+import jakarta.ws.rs.core.Response;
+
+/**
+ * This class provides a container vor carrying different types of values
+ */
+public class ValueContainer {
+
+    private Object value;
+    private ValueContainerType type;
+
+    private ValueContainer(Object value, ValueContainerType type) {
+        this.value = value;
+        this.type = type;
+    }
+
+    /**
+     * checks if the type of the contained value is the same as the typeToCheck
+     * @param typeToCheck the type to be checked if the contained value is of
+     * @throws InternalException if the types don't match an exception is thrown
+     */
+    private void checkType(ValueContainerType typeToCheck) throws InternalException {
+        if(this.type != typeToCheck) throw new InternalException("This ValueContainer ist not of the needed type " + typeToCheck + " its type is " + this.type + ".");
+    }
+
+    public static ValueContainer getInvalid() {
+        return new ValueContainer();
+    }
+
+    public static ValueContainer getVoid() {
+        return new ValueContainer((Void) null);
+    }
+
+    private ValueContainer() {
+        this(null, ValueContainerType.INVALID);
+    }
+
+    private ValueContainer(Void value) {
+        this(null, ValueContainerType.VOID);
+    }
+
+    /**
+     * Creates a ValueContainer of type int
+     * @param value the value contained by the container
+     */
+    public ValueContainer(int value) {
+        this(value, ValueContainerType.INT);
+    }
+
+    /**
+     * Creates a ValueContainer of type long
+     * @param value the value contained by the container
+     */
+    public ValueContainer(long value) {
+        this(value, ValueContainerType.LONG);
+    }
+
+    /**
+     * Creates a ValueContainer of type String
+     * @param value the value contained by the container
+     */
+    public ValueContainer(String value) {
+        this(value, ValueContainerType.STRING);
+    }
+
+    /**
+     * Creates a ValueContainer of type boolean
+     * @param value the value contained by the container
+     */
+    public ValueContainer(boolean value) {
+        this(value, ValueContainerType.BOOL);
+    }
+
+    /**
+     * Creates a ValueContainer of type Response
+     * @param value the value contained by the container
+     */
+    public ValueContainer(Response value) {
+        this(value, ValueContainerType.RESPONSE);
+    } 
+    
+    /**
+     * Creates a ValueContainer of type InputStream
+     * @param value the value contained by the container
+     */
+    public ValueContainer(InputStream value) {
+        this(value, ValueContainerType.INPUTSTREAM);
+    }
+
+    /**
+     * Informs about the type of the contained value
+     * @return
+     */
+    public ValueContainerType getType() {
+        return this.type;
+    }
+
+    /**
+     * Tries to return the value of the type int.
+     * @return
+     * @throws InternalException if the container has another type an exception will be thrown
+     */
+    public int getInt() throws InternalException {
+        this.checkType(ValueContainerType.INT);
+        return (int) this.value;
+    }
+
+    /**
+     * Tries to return the value of the type long.
+     * @return
+     * @throws InternalException if the container has another type an exception will be thrown
+     */
+    public long getLong() throws InternalException {
+        this.checkType(ValueContainerType.LONG);
+        return (long) this.value;
+    }
+
+    /**
+     * Tries to return the value of the type boolean.
+     * @return
+     * @throws InternalException if the container has another type an exception will be thrown
+     */
+    public boolean getBool() throws InternalException {
+        this.checkType(ValueContainerType.BOOL);
+        return (boolean) this.value;
+    }
+
+    /**
+     * Tries to return the value of the type String.
+     * @return
+     * @throws InternalException if the container has another type an exception will be thrown
+     */
+    public String getString() throws InternalException {
+        this.checkType(ValueContainerType.STRING);
+        return (String) this.value;
+    }
+
+    /**
+     * Tries to return the value of the type Response.
+     * @return
+     * @throws InternalException if the container has another type an exception will be thrown
+     */
+    public Response getResponse() throws InternalException {
+        this.checkType(ValueContainerType.RESPONSE);
+        return (Response) this.value;
+    }
+
+    /**
+     * Tries to return the value of the type InputStream.
+     * @return
+     * @throws InternalException if the container has another type an exception will be thrown
+     */
+    public InputStream getInputStream() throws InternalException {
+        this.checkType(ValueContainerType.INPUTSTREAM);
+        return (InputStream) this.value;
+    }
+
+    @Override
+    public String toString() {
+        switch(this.type) {
+            case INVALID: return ""+ValueContainerType.INVALID; 
+            case VOID: return ""+ValueContainerType.VOID;
+            case INT: return ""+this.value;
+            case LONG: return ""+this.value;
+            case BOOL: return ((boolean)this.value ? "true" : "false"); 
+            case STRING: return (String)this.value; 
+            case RESPONSE: return "Response " + ((Response) this.value).toString();
+            case INPUTSTREAM: return "An InputStream which will be printed here to prevent it from closing (and maybe it is too long).";
+            default:
+                throw new RuntimeException("Doesn't know how to make a String vom ValueContainer of type " + this.type + ". Please implement a new case is ValueContainer.toString().");
+        }
+    }
+
+    public boolean isNull() { return this.isInvalid() && this.value == null; }
+
+    public boolean isInvalid() { return this.type == ValueContainerType.INVALID; }
+
+    public boolean isVoid() { return this.type == ValueContainerType.VOID; }
+
+    
+
+
+}
diff --git a/src/main/java/org/icatproject/ids/models/DataInfoBase.java b/src/main/java/org/icatproject/ids/models/DataInfoBase.java
new file mode 100644
index 00000000..603a3e7e
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/models/DataInfoBase.java
@@ -0,0 +1,46 @@
+package org.icatproject.ids.models;
+
+/**
+ * A Base class for Data objct types. like Datasets or Datafiles
+ */
+public abstract class DataInfoBase {
+
+    protected long id;
+    protected String name;
+    protected String location;
+
+    protected DataInfoBase(long id, String name, String location){
+        this.name = name;
+        this.id = id;
+        this.location = location;
+    }
+
+    public abstract String toString();
+
+    public Long getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getLocation() {
+        return location;
+    }
+
+    public int hashCode() {
+        return (int) (this.id ^ (this.id >>> 32));
+    }
+
+    public boolean equals(Object obj) {
+        if (obj == this) {
+            return true;
+        }
+        if (obj == null || obj.getClass() != this.getClass()) {
+            return false;
+        }
+        return this.id == ((DataInfoBase) obj).getId();
+    }
+    
+}
diff --git a/src/main/java/org/icatproject/ids/models/DataSelection.java b/src/main/java/org/icatproject/ids/models/DataSelection.java
new file mode 100644
index 00000000..1bc59344
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/models/DataSelection.java
@@ -0,0 +1,74 @@
+package org.icatproject.ids.models;
+
+import java.util.List;
+import java.util.Set;
+import java.util.SortedMap;
+
+public class DataSelection {
+    protected SortedMap<Long, DataInfoBase> dsInfos;
+    protected SortedMap<Long, DataInfoBase> dfInfos;
+    protected Set<Long> emptyDatasets;
+    protected List<Long> invids;
+    protected List<Long> dsids;
+    protected List<Long> dfids;
+    protected Boolean zip;
+    protected Boolean compress;
+    private long length;
+
+
+
+    public DataSelection(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos, Set<Long> emptyDatasets, 
+        List<Long> invids2, List<Long> dsids, List<Long> dfids, long length, Boolean zip, Boolean compress) {
+
+        this.dsInfos = dsInfos;
+        this.dfInfos = dfInfos;
+        this.emptyDatasets = emptyDatasets;
+        this.invids = invids2;
+        this.dsids = dsids;
+        this.dfids = dfids;
+        this.length = length;
+        this.zip = zip;
+        this.compress = compress;
+    }
+
+
+    public SortedMap<Long, DataInfoBase> getDsInfo() {
+        return dsInfos;
+    }
+
+
+    public SortedMap<Long, DataInfoBase> getDfInfo() {
+        return dfInfos;
+    }
+
+    public Boolean getZip() {
+        return this.zip;
+    }
+
+    public Boolean getCompress() {
+        return this.compress;
+    }
+
+    public long getLength() {
+        return this.length;
+    }
+
+
+    public boolean mustZip() {
+        // if(this.zip == null) {
+            return dfids.size() > 1L || !dsids.isEmpty() || !invids.isEmpty()
+                    || (dfids.isEmpty() && dsids.isEmpty() && invids.isEmpty());
+        // }
+
+        // return this.zip;
+    }
+
+    public boolean isSingleDataset() {
+        return dfids.isEmpty() && dsids.size() == 1 && invids.isEmpty();
+    }
+
+
+    public Set<Long> getEmptyDatasets() {
+        return emptyDatasets;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/models/DatafileInfo.java b/src/main/java/org/icatproject/ids/models/DatafileInfo.java
new file mode 100644
index 00000000..789cfa79
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/models/DatafileInfo.java
@@ -0,0 +1,58 @@
+package org.icatproject.ids.models;
+
+import org.icatproject.ids.plugin.DfInfo;
+
+/**
+ * Contains information about a Datafile. Replaces DsInfo in v3
+ * May should implement DfInfo interface
+ */
+public class DatafileInfo extends DataInfoBase implements Comparable<DatafileInfo>, DfInfo {
+
+    protected String createId;
+    protected String modId; 
+    protected long datasId;
+
+    public DatafileInfo(Long id, String name, String location, String createId, String modId, Long datasId) {
+        super(id, name, location);
+
+        this.createId = createId;
+        this.modId = modId;
+        this.datasId = datasId;
+    }
+
+    public String getCreateId() {
+        return this.createId;
+    }
+
+    public String getModId() {
+        return this.modId;
+    }
+
+    public long getDsId() {
+        return this.datasId;
+    }
+
+    @Override
+    public String toString() {
+        return this.location;
+    }
+
+    @Override
+    public int compareTo(DatafileInfo o) {
+        if (this.id > o.getId()) {
+            return 1;
+        }
+        if (this.id < o.getId()) {
+            return -1;
+        }
+        return 0;
+    }
+
+    // implementing DfInfo
+    @Override
+    public Long getDfId() { return this.getId(); }
+    @Override
+    public String getDfLocation() { return this.getLocation(); }
+    @Override
+    public String getDfName() { return this.getName(); }
+}
diff --git a/src/main/java/org/icatproject/ids/models/DatasetInfo.java b/src/main/java/org/icatproject/ids/models/DatasetInfo.java
new file mode 100644
index 00000000..be4d9a77
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/models/DatasetInfo.java
@@ -0,0 +1,95 @@
+package org.icatproject.ids.models;
+
+import org.icatproject.Dataset;
+import org.icatproject.Facility;
+import org.icatproject.Investigation;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.plugin.DsInfo;
+
+/**
+ * Contains information about a Dataset. Replaces DsInfo in v3.
+ * May should implement DsInfo interface
+ */
+public class DatasetInfo extends DataInfoBase implements DsInfo {
+
+    protected Long facilityId;
+    protected String facilityName;
+    protected Long investigationId;
+    protected String investigationName;
+    protected String visitId;
+
+
+    public DatasetInfo(Dataset ds) throws InsufficientPrivilegesException {
+        super(ds.getId(), ds.getName(), ds.getLocation()); 
+
+        Investigation investigation = ds.getInvestigation();
+        if (investigation == null) {
+            throw new InsufficientPrivilegesException(
+                    "Probably not able to read Investigation for dataset id " + ds.getId());
+        }
+        Facility facility = investigation.getFacility();
+        if (facility == null) {
+            throw new InsufficientPrivilegesException(
+                    "Probably not able to read Facility for investigation id "
+                            + investigation.getId());
+        }
+
+        this.investigationId = investigation.getId();
+        this.investigationName = investigation.getName();
+        this.visitId = investigation.getVisitId();
+        this.facilityId = facility.getId();
+        this.facilityName = facility.getName();
+    }
+
+
+    public DatasetInfo(Long id, String name, String location, Long investigationId, String investigationName, String visitId, Long facilityId, String facilityName) {
+        super(id, name, location);
+
+        this.facilityId = facilityId;
+        this.facilityName = facilityName;
+        this.investigationId = investigationId;
+        this.investigationName = investigationName;
+        this.visitId = visitId;
+    }
+
+    @Override
+    public String toString() {
+        return this.investigationId + "/" + this.id + " (" + this.facilityName + "/" + this.investigationName + "/" + this.visitId + "/"
+                + this.name + ")";
+    }
+
+    public Long getFacilityId() {
+        return facilityId;
+    }
+
+    public String getFacilityName() {
+        return facilityName;
+    }
+
+    public Long getInvestigationId() {
+        return investigationId;
+    }
+
+    public String getInvestigationName() {
+        return investigationName;
+    }
+
+    public String getVisitId() {
+        return visitId;
+    }
+
+
+    // implementing DsInfo
+
+    @Override
+    public Long getDsId() { return this.getId(); }
+    @Override
+    public String getDsName() { return this.getName(); }
+    @Override
+    public String getDsLocation() { return this.getLocation(); }
+    @Override
+    public Long getInvId() { return this.getInvestigationId(); }
+    @Override
+    public String getInvName() { return this.getInvestigationName(); }
+
+}
diff --git a/src/main/java/org/icatproject/ids/models/Prepared.java b/src/main/java/org/icatproject/ids/models/Prepared.java
new file mode 100644
index 00000000..5e04d830
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/models/Prepared.java
@@ -0,0 +1,145 @@
+package org.icatproject.ids.models;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.TreeMap;
+
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import jakarta.json.Json;
+import jakarta.json.JsonNumber;
+import jakarta.json.JsonObject;
+import jakarta.json.JsonReader;
+import jakarta.json.JsonValue;
+import jakarta.json.stream.JsonGenerator;
+
+/* This is a POJO with only package access so don't make data private */
+public class Prepared {
+
+    protected final static Logger logger = LoggerFactory.getLogger(RequestHandlerBase.class);
+
+    
+    public SortedMap<Long, DataInfoBase> dsInfos;
+    public SortedMap<Long, DataInfoBase> dfInfos;
+    public Set<Long> emptyDatasets;
+    public long fileLength;
+    public boolean zip;
+    public boolean compress;
+
+    public Prepared(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos, Set<Long> emptyDatasets, long fileLength) {
+        this.dsInfos = dsInfos;
+        this.dfInfos = dfInfos;
+        this.emptyDatasets = emptyDatasets;
+        this.fileLength = fileLength;
+        this.zip = false;
+        this.compress = false;
+    }
+
+    public Prepared(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos, Set<Long> emptyDatasets, long fileLength, Boolean zip, Boolean compress) {
+        this(dsInfos, dfInfos, emptyDatasets, fileLength);
+        this.zip = zip;
+        this.compress = compress;
+    }
+
+
+    public static void pack(OutputStream stream, boolean zip, boolean compress, Map<Long, DataInfoBase> dsInfos,
+                        Map<Long, DataInfoBase> dfInfos, Set<Long> emptyDatasets, long fileLength) {
+        JsonGenerator gen = Json.createGenerator(stream);
+        gen.writeStartObject();
+        gen.write("zip", zip);
+        gen.write("compress", compress);
+        gen.write("fileLength", fileLength);
+
+        gen.writeStartArray("dsInfo");
+        for (DataInfoBase dataInfo : dsInfos.values()) {
+            var dsInfo = (DatasetInfo)dataInfo;
+            logger.debug("dsInfo " + dsInfo);
+            gen.writeStartObject().write("dsId", dsInfo.getId())
+
+                    .write("dsName", dsInfo.getDsName()).write("facilityId", dsInfo.getFacilityId())
+                    .write("facilityName", dsInfo.getFacilityName()).write("invId", dsInfo.getInvId())
+                    .write("invName", dsInfo.getInvName()).write("visitId", dsInfo.getVisitId());
+            if (dsInfo.getDsLocation() != null) {
+                gen.write("dsLocation", dsInfo.getDsLocation());
+            } else {
+                gen.writeNull("dsLocation");
+            }
+            gen.writeEnd();
+        }
+        gen.writeEnd();
+
+        gen.writeStartArray("dfInfo");
+        for (DataInfoBase dataInfo : dfInfos.values()) {
+            var dfInfo = (DatafileInfo)dataInfo;
+            DataInfoBase dsInfo = dsInfos.get(dfInfo.getDsId());
+            gen.writeStartObject().write("dsId", dsInfo.getId()).write("dfId", dfInfo.getId())
+                    .write("dfName", dfInfo.getDfName()).write("createId", dfInfo.getCreateId())
+                    .write("modId", dfInfo.getModId());
+            if (dfInfo.getDfLocation() != null) {
+                gen.write("dfLocation", dfInfo.getDfLocation());
+            } else {
+                gen.writeNull("dfLocation");
+            }
+            gen.writeEnd();
+
+        }
+        gen.writeEnd();
+
+        gen.writeStartArray("emptyDs");
+        for (Long emptyDs : emptyDatasets) {
+            gen.write(emptyDs);
+        }
+        gen.writeEnd();
+
+        gen.writeEnd().close();
+
+    }
+
+
+    public static Prepared unpack(InputStream stream) throws InternalException {
+
+        JsonObject pd;
+        try (JsonReader jsonReader = Json.createReader(stream)) {
+            pd = jsonReader.readObject();
+        }
+        var zip = pd.getBoolean("zip");
+        var compress = pd.getBoolean("compress");
+        var fileLength = pd.containsKey("fileLength") ? pd.getInt("fileLength") : 0;
+        SortedMap<Long, DataInfoBase> dsInfos = new TreeMap<>();
+        SortedMap<Long, DataInfoBase> dfInfos = new TreeMap<>();
+        Set<Long> emptyDatasets = new HashSet<>();
+
+        for (JsonValue itemV : pd.getJsonArray("dfInfo")) {
+            JsonObject item = (JsonObject) itemV;
+            String dfLocation = item.isNull("dfLocation") ? null : item.getString("dfLocation");
+            long dfid = item.getJsonNumber("dfId").longValueExact();
+            dfInfos.put(dfid, new DatafileInfo(dfid, item.getString("dfName"),
+                    dfLocation, item.getString("createId"), item.getString("modId"),
+                    item.getJsonNumber("dsId").longValueExact()));
+
+        }
+
+        for (JsonValue itemV : pd.getJsonArray("dsInfo")) {
+            JsonObject item = (JsonObject) itemV;
+            long dsId = item.getJsonNumber("dsId").longValueExact();
+            String dsLocation = item.isNull("dsLocation") ? null : item.getString("dsLocation");
+            dsInfos.put(dsId, new DatasetInfo(dsId, item.getString("dsName"), dsLocation,
+                    item.getJsonNumber("invId").longValueExact(), item.getString("invName"), item.getString("visitId"),
+                    item.getJsonNumber("facilityId").longValueExact(), item.getString("facilityName")));
+        }
+
+        for (JsonValue itemV : pd.getJsonArray("emptyDs")) {
+            emptyDatasets.add(((JsonNumber) itemV).longValueExact());
+        }
+
+        return new Prepared(dsInfos, dfInfos, emptyDatasets, fileLength, zip, compress);
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/ArchiveHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/ArchiveHandler.java
new file mode 100644
index 00000000..032e8437
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/ArchiveHandler.java
@@ -0,0 +1,31 @@
+package org.icatproject.ids.requestHandlers;
+
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+public class ArchiveHandler extends DataRequestHandler {
+
+    public ArchiveHandler(String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.ARCHIVE, ip, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService) throws NotImplementedException, InternalException {
+        
+        dataSelectionService.scheduleTasks(DeferredOp.ARCHIVE);
+        return ValueContainer.getVoid();
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.MIGRATE;
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/DeleteHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/DeleteHandler.java
new file mode 100644
index 00000000..a4cb44a9
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/DeleteHandler.java
@@ -0,0 +1,91 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.icatproject.Datafile;
+import org.icatproject.EntityBaseBean;
+import org.icatproject.IcatExceptionType;
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.enums.StorageUnit;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.plugin.AlreadyLockedException;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.icatproject.ids.services.LockManager.LockType;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+
+public class DeleteHandler extends DataRequestHandler {
+
+    public DeleteHandler(String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.DELETE, ip, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        if (readOnly) {
+            throw new NotImplementedException("This operation has been configured to be unavailable");
+        }
+
+        var serviceProvider = ServiceProvider.getInstance();
+
+        // Do it
+        try (Lock lock = serviceProvider.getLockManager().lock(dataSelectionService.getDsInfo().values(), LockType.EXCLUSIVE)) {
+            if (storageUnit == StorageUnit.DATASET) {
+                dataSelectionService.checkOnline();
+            }
+
+            /* Now delete from ICAT */
+            List<EntityBaseBean> dfs = new ArrayList<>();
+            for (DataInfoBase dfInfo : dataSelectionService.getDfInfo().values()) {
+                Datafile df = new Datafile();
+                df.setId(dfInfo.getId());
+                dfs.add(df);
+            }
+            try {
+                serviceProvider.getIcat().deleteMany(this.dataController.getOperationId(), dfs);
+            } catch (IcatException_Exception e) {
+                IcatExceptionType type = e.getFaultInfo().getType();
+
+                if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
+                    throw new InsufficientPrivilegesException(e.getMessage());
+                }
+                if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
+                    throw new NotFoundException(e.getMessage());
+                }
+                throw new InternalException(type + " " + e.getMessage());
+            }
+
+            dataSelectionService.delete();
+
+        } catch (AlreadyLockedException e) {
+            logger.debug("Could not acquire lock, delete failed");
+            throw new DataNotOnlineException("Data is busy");
+        } catch (IOException e) {
+            logger.error("I/O error " + e.getMessage());
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+
+        return ValueContainer.getVoid();
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.WRITE;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/GetDataFileIdsHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/GetDataFileIdsHandler.java
new file mode 100644
index 00000000..7c22c38f
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/GetDataFileIdsHandler.java
@@ -0,0 +1,57 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.io.ByteArrayOutputStream;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.requestHandlers.base.PreparedDataController;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+import jakarta.json.Json;
+import jakarta.json.stream.JsonGenerator;
+
+public class GetDataFileIdsHandler extends DataRequestHandler {
+
+    public GetDataFileIdsHandler(String ip, String preparedId, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.GETDATAFILEIDS, ip, preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
+
+            if(this.dataController instanceof PreparedDataController) {
+                gen.write("zip", dataSelectionService.getZip());
+                gen.write("compress", dataSelectionService.getCompress());
+            }
+
+            gen.writeStartArray("ids");
+            for (DataInfoBase dfInfo : dataSelectionService.getDfInfo().values()) {
+                gen.write(dfInfo.getId());
+            }
+            gen.writeEnd().writeEnd().close();
+        }
+        String resp = baos.toString();
+
+        return new ValueContainer(resp);
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/GetDataHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/GetDataHandler.java
new file mode 100644
index 00000000..8cdb64ce
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/GetDataHandler.java
@@ -0,0 +1,207 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.text.SimpleDateFormat;
+import java.util.Collection;
+import java.util.Date;
+import java.util.OptionalLong;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.IdsException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.SO;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.plugin.AlreadyLockedException;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.icatproject.ids.services.LockManager.LockType;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+import jakarta.json.stream.JsonGenerator;
+import jakarta.ws.rs.core.Response;
+import static jakarta.ws.rs.core.HttpHeaders.CONTENT_LENGTH;
+
+public class GetDataHandler extends DataRequestHandler {
+
+    private Pattern rangeRe;
+    private static AtomicLong transferIdCounter = new AtomicLong();
+
+    Boolean compress;
+    Boolean zip;
+    String outname;
+    String range;
+    Long transferId;
+
+    public GetDataHandler(String ip, String preparedId, String sessionId, String investigationIds, String datasetIds, String datafileIds, Boolean compress, Boolean zip, String outname, String range) {
+        super(RequestType.GETDATA, ip, preparedId, sessionId, investigationIds, datasetIds, datafileIds );
+
+        this.initializeAdditionallParameters(sessionId, compress, zip, outname, range);
+    }
+
+    private void initializeAdditionallParameters(String sessionId, Boolean compress, Boolean zip, String outname, String range) {
+        
+        this.outname = outname;
+        this.range = range;
+        this.transferId = null;
+        this.rangeRe = Pattern.compile("bytes=(\\d+)-");
+
+        if(sessionId != null) {
+            this.compress = compress;
+            this.zip = zip;
+        }
+    }
+
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService) throws InternalException, NotImplementedException, BadRequestException, NotFoundException, InsufficientPrivilegesException, DataNotOnlineException  {
+
+        if(this.compress == null || this.zip == null) {
+            this.zip = dataSelectionService.getZip();
+            this.compress = dataSelectionService.getCompress();
+        }
+
+        long offset = 0;
+        if ( range != null) {
+
+            Matcher m = rangeRe.matcher(range);
+            if (!m.matches()) {
+                throw new BadRequestException("The range must match " + rangeRe.pattern());
+            }
+            offset = Long.parseLong(m.group(1));
+            logger.debug("Range " + range + " -> offset " + offset);
+        }
+
+        return new ValueContainer(this.getData(dataSelectionService, offset));
+    }
+
+
+    private Response getData(DataSelectionService dataSelectionService, final long offset) throws BadRequestException,
+            NotFoundException, InternalException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        long start = System.currentTimeMillis();
+        
+        var length = this.zip ? OptionalLong.empty() : dataSelectionService.getFileLength();
+
+        final boolean finalZip = this.dataController.mustZip(zip, dataSelectionService); 
+
+        Lock lock = null;
+        try {
+            var serviceProvider = ServiceProvider.getInstance();
+            lock = serviceProvider.getLockManager().lock(dataSelectionService.getDsInfo().values(), LockType.SHARED);
+
+            if (twoLevel) {
+                dataSelectionService.checkOnline();
+            }
+            checkDatafilesPresent(dataSelectionService.getDfInfo().values());
+
+            /* Construct the name to include in the headers */
+            String name;
+            if (outname == null) {
+                if (finalZip) {
+                    name = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss").format(new Date()) + ".zip";
+                } else {
+                    name = dataSelectionService.getDfInfo().values().iterator().next().getName();
+                }
+            } else {
+                if (finalZip) {
+                    String ext = outname.substring(outname.lastIndexOf(".") + 1, outname.length());
+                    if ("zip".equals(ext)) {
+                        name = outname;
+                    } else {
+                        name = outname + ".zip";
+                    }
+                } else {
+                    name = outname;
+                }
+            }
+
+            if (ServiceProvider.getInstance().getPropertyHandler().getLogSet().contains(this.getCallType())) {
+                transferId = transferIdCounter.getAndIncrement();
+            }
+
+            var response = Response.status(offset == 0 ? HttpURLConnection.HTTP_OK : HttpURLConnection.HTTP_PARTIAL)
+                    .entity(new SO(dataSelectionService.getDsInfo(), dataSelectionService.getDfInfo(), offset, finalZip, compress, lock, transferId, ip, start, serviceProvider))
+                    .header("Content-Disposition", "attachment; filename=\"" + name + "\"").header("Accept-Ranges", "bytes");
+            length.stream()
+                    .map(l -> Math.max(0L, l - offset))
+                    .forEach(l -> response.header(CONTENT_LENGTH, l));
+                
+            return response.build();
+
+        } catch (AlreadyLockedException e) {
+            logger.debug("Could not acquire lock, getData failed");
+            throw new DataNotOnlineException("Data is busy");
+        } catch (IOException e) {
+            // if (lock != null) {
+            //     lock.release();
+            // }
+            logger.error("I/O error " + e.getMessage());
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        } catch (IdsException e) {
+            lock.release();
+            throw e;
+        }
+    }
+
+
+    private void checkDatafilesPresent(Collection<DataInfoBase> dfInfos)
+            throws NotFoundException, InternalException {
+
+        var serviceProvider = ServiceProvider.getInstance();
+        /* Check that datafiles have not been deleted before locking */
+        int n = 0;
+        StringBuffer sb = new StringBuffer("SELECT COUNT(df) from Datafile df WHERE (df.id in (");
+        for (DataInfoBase dfInfo : dfInfos) {
+            if (n != 0) {
+                sb.append(',');
+            }
+            sb.append(dfInfo.getId());
+            if (++n == serviceProvider.getPropertyHandler().getMaxIdsInQuery()) {
+                try {
+                    if (((Long) serviceProvider.getIcatReader().search(sb.append("))").toString()).get(0)).intValue() != n) {
+                        throw new NotFoundException("One of the data files requested has been deleted");
+                    }
+                    n = 0;
+                    sb = new StringBuffer("SELECT COUNT(df) from Datafile df WHERE (df.id in (");
+                } catch (IcatException_Exception e) {
+                    throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
+                }
+            }
+        }
+        if (n != 0) {
+            try {
+                if (((Long) serviceProvider.getIcatReader().search(sb.append("))").toString()).get(0)).intValue() != n) {
+                    throw new NotFoundException("One of the datafiles requested has been deleted");
+                }
+            } catch (IcatException_Exception e) {
+                throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
+            }
+        }
+
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.READ;
+    }
+
+    @Override
+    public void addCustomParametersToTransmitterJSON(JsonGenerator gen) {
+        if(transferId == null) transferId = -1L;
+        gen.write("transferId", transferId);
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/GetIcatUrlHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/GetIcatUrlHandler.java
new file mode 100644
index 00000000..94a78919
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/GetIcatUrlHandler.java
@@ -0,0 +1,36 @@
+package org.icatproject.ids.requestHandlers;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+import org.icatproject.ids.services.ServiceProvider;
+
+
+public class GetIcatUrlHandler extends RequestHandlerBase {
+
+    public GetIcatUrlHandler(String ip) {
+        super(RequestType.GETICATURL, ip);
+    }
+
+    @Override
+    public ValueContainer handleRequest()
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        var propertyHandler = ServiceProvider.getInstance().getPropertyHandler();
+        return new ValueContainer(propertyHandler.getIcatUrl());
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/GetServiceStatusHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/GetServiceStatusHandler.java
new file mode 100644
index 00000000..713c3603
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/GetServiceStatusHandler.java
@@ -0,0 +1,66 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.util.Set;
+
+import org.icatproject.IcatExceptionType;
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+import org.icatproject.ids.services.ServiceProvider;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class GetServiceStatusHandler extends RequestHandlerBase {
+
+    private Set<String> rootUserNames;
+    private String sessionId;
+    private ServiceProvider serviceProvider;
+
+    public GetServiceStatusHandler(String ip, String sessionId) {
+        super(RequestType.GETSERVICESTATUS, ip);
+
+        this.sessionId = sessionId;
+        rootUserNames = ServiceProvider.getInstance().getPropertyHandler().getRootUserNames();
+        this.serviceProvider = ServiceProvider.getInstance();
+    }
+
+    @Override
+    public ValueContainer handleRequest()
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        try {
+            String uname = serviceProvider.getIcat().getUserName(sessionId);
+            if (!rootUserNames.contains(uname)) {
+                throw new InsufficientPrivilegesException(uname + " is not included in the ids rootUserNames set.");
+            }
+        } catch (IcatException_Exception e) {
+            IcatExceptionType type = e.getFaultInfo().getType();
+            if (type == IcatExceptionType.SESSION) {
+                throw new InsufficientPrivilegesException(e.getClass() + " " + e.getMessage());
+            }
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+
+        return new ValueContainer(serviceProvider.getFsm().getServiceStatus());
+    }
+
+    @Override
+    public void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {
+        gen.write("userName", serviceProvider.getIcat().getUserName(sessionId));
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/GetStatusHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/GetStatusHandler.java
new file mode 100644
index 00000000..9da9787c
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/GetStatusHandler.java
@@ -0,0 +1,58 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.util.Set;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.enums.Status;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+public class GetStatusHandler extends DataRequestHandler {
+
+    public GetStatusHandler(String ip, String preparedId, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.GETSTATUS, ip, preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        Status status = Status.ONLINE;
+        var serviceProvider = ServiceProvider.getInstance();
+
+        Set<DataInfoBase> restoring = serviceProvider.getFsm().getRestoring();
+        Set<DataInfoBase> maybeOffline = serviceProvider.getFsm().getMaybeOffline();
+        for (DataInfoBase dataInfo : dataSelectionService.getPrimaryDataInfos().values()) {
+            serviceProvider.getFsm().checkFailure(dataInfo.getId());
+            if (restoring.contains(dataInfo)) {
+                status = Status.RESTORING;
+            } else if (maybeOffline.contains(dataInfo)) {
+                status = Status.ARCHIVED;
+                break;
+            } else if (!dataSelectionService.existsInMainStorage(dataInfo)) {
+                status = Status.ARCHIVED;
+                break;
+            }
+        }
+
+        logger.debug("Status is " + status.name());
+
+        return new ValueContainer(status.name());
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/IsPreparedHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/IsPreparedHandler.java
new file mode 100644
index 00000000..6f2deba7
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/IsPreparedHandler.java
@@ -0,0 +1,82 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+import java.util.concurrent.locks.ReentrantLock;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+public class IsPreparedHandler extends DataRequestHandler {
+
+    public IsPreparedHandler(String ip, String preparedId) {
+        super(RequestType.ISPREPARED, ip, preparedId);
+    }
+
+    class PreparedStatus {
+        public ReentrantLock lock = new ReentrantLock();
+        public Long fromElement;
+        public Future<?> future;
+
+    }
+
+    private Map<String, PreparedStatus> preparedStatusMap = new ConcurrentHashMap<>();
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        // Do it
+        boolean prepared = true;
+
+        PreparedStatus status = preparedStatusMap.computeIfAbsent(this.dataController.getOperationId(), k -> new PreparedStatus());
+
+        if (!status.lock.tryLock()) {
+            logger.debug("Lock held for evaluation of isPrepared for preparedId {}", this.dataController.getOperationId());
+            return new ValueContainer(false);
+        }
+        try {
+            Future<?> future = status.future;
+            if (future != null) {
+                if (future.isDone()) {
+                    try {
+                        future.get();
+                    } catch (ExecutionException e) {
+                        throw new InternalException(e.getClass() + " " + e.getMessage());
+                    } catch (InterruptedException e) {
+                        // Ignore
+                    } finally {
+                        status.future = null;
+                    }
+                } else {
+                    logger.debug("Background process still running for preparedId {}", this.dataController.getOperationId());
+                    return new ValueContainer(false);
+                }
+            }
+
+            prepared = dataSelectionService.isPrepared(this.dataController.getOperationId());
+
+            return new ValueContainer(prepared);
+
+        } finally {
+            status.lock.unlock();
+        }
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/IsReadOnlyHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/IsReadOnlyHandler.java
new file mode 100644
index 00000000..a7acf20e
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/IsReadOnlyHandler.java
@@ -0,0 +1,33 @@
+package org.icatproject.ids.requestHandlers;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+
+public class IsReadOnlyHandler extends RequestHandlerBase {
+    
+    public IsReadOnlyHandler(String ip) {
+        super(RequestType.ISREADONLY, ip);
+
+    }
+
+    @Override
+    public ValueContainer handleRequest()
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        return new ValueContainer(this.readOnly);
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/IsTwoLevelHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/IsTwoLevelHandler.java
new file mode 100644
index 00000000..f9cc3be1
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/IsTwoLevelHandler.java
@@ -0,0 +1,32 @@
+package org.icatproject.ids.requestHandlers;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+
+public class IsTwoLevelHandler extends RequestHandlerBase {
+
+    public IsTwoLevelHandler(String ip) {
+        super(RequestType.ISTWOLEVEL, ip);
+    }
+
+    @Override
+    public ValueContainer handleRequest()
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+        
+        return new ValueContainer(twoLevel);
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/PrepareDataHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/PrepareDataHandler.java
new file mode 100644
index 00000000..625c4ac2
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/PrepareDataHandler.java
@@ -0,0 +1,85 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.io.BufferedOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.file.Files;
+import java.util.UUID;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestIdNames;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.Prepared;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class PrepareDataHandler extends DataRequestHandler {
+
+    Boolean compress;
+    Boolean zip;
+    String preparedId;
+
+    public PrepareDataHandler(String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds, Boolean compress, Boolean zip) {
+        super(RequestType.PREPAREDATA,ip, sessionId, investigationIds, datasetIds, datafileIds);
+
+        this.zip = zip;
+        this.compress = compress;
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException { 
+
+        preparedId = UUID.randomUUID().toString();
+        
+        dataSelectionService.restoreDataInfos();
+
+        if (dataSelectionService.mustZip()) {
+            zip = true;
+        }
+
+        logger.debug("Writing to " + preparedDir.resolve(preparedId));
+        try (OutputStream stream = new BufferedOutputStream(Files.newOutputStream(preparedDir.resolve(preparedId)))) {
+            Prepared.pack(  stream, 
+                            zip,
+                            compress, 
+                            dataSelectionService.getDsInfo(), 
+                            dataSelectionService.getDfInfo(), 
+                            dataSelectionService.getEmptyDatasets(), 
+                            dataSelectionService.getFileLength().isEmpty() ? 0 : dataSelectionService.getFileLength().getAsLong()
+            );
+        } catch (IOException e) {
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+
+        logger.debug("preparedId is " + preparedId);
+
+        return new ValueContainer(preparedId);
+    }
+
+    @Override
+    public String addCustomParametersToLogString() { 
+        return "zip='" + this.zip + "'' compress='" + compress + "'";
+    }
+
+    @Override
+    public void addCustomParametersToTransmitterJSON(JsonGenerator gen) {
+        if(preparedId == null) preparedId = "";
+        gen.write(RequestIdNames.preparedId, preparedId);
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.PREPARE;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/PutHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/PutHandler.java
new file mode 100644
index 00000000..3e9bfbd9
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/PutHandler.java
@@ -0,0 +1,367 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.security.NoSuchAlgorithmException;
+import java.util.GregorianCalendar;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.TreeMap;
+import java.util.zip.CRC32;
+import javax.xml.datatype.DatatypeFactory;
+
+import org.icatproject.Datafile;
+import org.icatproject.DatafileFormat;
+import org.icatproject.Dataset;
+import org.icatproject.ICAT;
+import org.icatproject.IcatExceptionType;
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestIdNames;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.enums.StorageUnit;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.IdsException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.CheckedWithSizeInputStream;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.plugin.AlreadyLockedException;
+import org.icatproject.ids.requestHandlers.base.DataControllerBase;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.icatproject.ids.services.LockManager.LockType;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionServiceFactory;
+import org.icatproject.utils.IcatSecurity;
+
+import jakarta.json.Json;
+import jakarta.json.stream.JsonGenerator;
+import jakarta.ws.rs.core.Response;
+
+public class PutHandler extends RequestHandlerBase {
+
+    String sessionId;
+    InputStream body;
+    String name;
+    String datafileFormatIdString;
+    String datasetIdString;
+    String description;
+    String doi;
+    String datafileCreateTimeString;
+    String datafileModTimeString;
+    boolean wrap;
+    boolean padding;
+
+    private Long dfId;
+    private ServiceProvider serviceProvider;
+    private DatatypeFactory datatypeFactory;
+    private static String paddedPrefix;
+    private static final String prefix = "<html><script type=\"text/javascript\">window.name='";
+    private static final String suffix = "';</script></html>";
+
+    static {
+        paddedPrefix = "<html><script type=\"text/javascript\">/*";
+        for (int n = 1; n < 25; n++) {
+            paddedPrefix += " *        \n";
+        }
+        paddedPrefix += "*/window.name='";
+    }
+
+    public PutHandler(  String ip, String sessionId, InputStream body, String name, String datafileFormatIdString,
+                        String datasetIdString, String description, String doi, String datafileCreateTimeString,
+                        String datafileModTimeString, boolean wrap, boolean padding) {
+        super(RequestType.PUT, ip);
+
+        this.sessionId = sessionId;
+        this.body = body;
+        this.name = name;
+        this.datafileFormatIdString = datafileFormatIdString;
+        this.datasetIdString = datasetIdString;
+        this.description = description;
+        this.doi = doi;
+        this.datafileCreateTimeString = datafileCreateTimeString;
+        this.datafileModTimeString = datafileModTimeString;
+        this.wrap = wrap;
+        this.padding = padding;
+
+        this.dfId = -1L;
+        this.serviceProvider = ServiceProvider.getInstance();
+
+        try {
+
+            this.datatypeFactory = DatatypeFactory.newInstance();
+
+        } catch (Throwable e) {
+            logger.error("Won't start ", e);
+            throw new RuntimeException("PutHandler reports " + e.getClass() + " " + e.getMessage());
+        }
+    }
+
+    @Override
+    public ValueContainer handleRequest()
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        try {
+
+            if (readOnly) {
+                throw new NotImplementedException("This operation has been configured to be unavailable");
+            }
+
+            DataControllerBase.validateUUID(RequestIdNames.sessionId, sessionId);
+            if (name == null) {
+                throw new BadRequestException("The name parameter must be set");
+            }
+
+            if (datafileFormatIdString == null) {
+                throw new BadRequestException("The datafileFormatId parameter must be set");
+            }
+            long datafileFormatId;
+            try {
+                datafileFormatId = Long.parseLong(datafileFormatIdString);
+            } catch (NumberFormatException e) {
+                throw new BadRequestException("The datafileFormatId parameter must be numeric");
+            }
+
+            if (datasetIdString == null) {
+                throw new BadRequestException("The datasetId parameter must be set");
+            }
+            long datasetId;
+            try {
+                datasetId = Long.parseLong(datasetIdString);
+            } catch (NumberFormatException e) {
+                throw new BadRequestException("The datasetId parameter must be numeric");
+            }
+
+            Long datafileCreateTime = null;
+            if (datafileCreateTimeString != null) {
+                try {
+                    datafileCreateTime = Long.parseLong(datafileCreateTimeString);
+                } catch (NumberFormatException e) {
+                    throw new BadRequestException("The datafileCreateTime parameter must be numeric");
+                }
+            }
+
+            Long datafileModTime = null;
+            if (datafileModTimeString != null) {
+                try {
+                    datafileModTime = Long.parseLong(datafileModTimeString);
+                } catch (NumberFormatException e) {
+                    throw new BadRequestException("The datafileModTime parameter must be numeric");
+                }
+            }
+
+            // Do it
+            Dataset ds;
+            try {
+                ds = (Dataset) serviceProvider.getIcat().get(sessionId, "Dataset INCLUDE Investigation, Facility", datasetId);
+            } catch (IcatException_Exception e) {
+                IcatExceptionType type = e.getFaultInfo().getType();
+                if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
+                    throw new InsufficientPrivilegesException(e.getMessage());
+                }
+                if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
+                    throw new NotFoundException(e.getMessage());
+                }
+                throw new InternalException(type + " " + e.getMessage());
+            }
+
+            DatasetInfo dsInfo = new DatasetInfo(ds);
+            try (Lock lock = serviceProvider.getLockManager().lock(dsInfo, LockType.SHARED)) {
+                if (storageUnit == StorageUnit.DATASET) {
+                    var dfInfos = new TreeMap<Long, DataInfoBase>();
+                    Set<Long> emptyDatasets = new HashSet<>();
+                    try {
+                        List<Object> counts = serviceProvider.getIcat().search(sessionId,
+                                "COUNT(Datafile) <-> Dataset [id=" + dsInfo.getId() + "]");
+                        if ((Long) counts.get(0) == 0) {
+                            emptyDatasets.add(dsInfo.getId());
+                        }
+                    } catch (IcatException_Exception e) {
+                        IcatExceptionType type = e.getFaultInfo().getType();
+                        if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
+                            throw new InsufficientPrivilegesException(e.getMessage());
+                        }
+                        if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
+                            throw new NotFoundException(e.getMessage());
+                        }
+                        throw new InternalException(type + " " + e.getMessage());
+                    }
+                    var dsInfos = new TreeMap<Long, DataInfoBase>();
+                    dsInfos.put(dsInfo.getId(), dsInfo);
+                    DataSelectionService dataSelectionService = DataSelectionServiceFactory.getService(dsInfos, dfInfos, emptyDatasets, 0, this.getRequestType());
+                    dataSelectionService.checkOnline();
+                }
+
+                CRC32 crc = new CRC32();
+                CheckedWithSizeInputStream is = new CheckedWithSizeInputStream(body, crc);
+                String location;
+                try {
+                    location = serviceProvider.getMainStorage().put(dsInfo, name, is);
+                } catch (IllegalArgumentException e) {
+                    throw new BadRequestException("Illegal filename or dataset: " + e.getMessage());
+                }
+                is.close();
+                long checksum = crc.getValue();
+                long size = is.getSize();
+                
+                try {
+                    dfId = registerDatafile(sessionId, name, datafileFormatId, location, checksum, size, ds,
+                            description, doi, datafileCreateTime, datafileModTime);
+                } catch (InsufficientPrivilegesException | NotFoundException | InternalException
+                         | BadRequestException e) {
+                    logger.debug("Problem with registration " + e.getClass() + " " + e.getMessage()
+                            + " datafile will now be deleted");
+                    String userId = null;
+                    try {
+                        userId = serviceProvider.getIcat().getUserName(sessionId);
+                    } catch (IcatException_Exception e1) {
+                        logger.error("Unable to get user name for session " + sessionId + " so mainStorage.delete of "
+                                + location + " may fail");
+                    }
+                    serviceProvider.getMainStorage().delete(location, userId, userId);
+                    throw e;
+                }
+
+                if (storageUnit == StorageUnit.DATASET) {
+                    serviceProvider.getFsm().queue(dsInfo, DeferredOp.WRITE);
+                } else if (storageUnit == StorageUnit.DATAFILE) {
+                    Datafile df;
+                    try {
+                        df = (Datafile) serviceProvider.getIcatReader().get("Datafile", dfId);
+                    } catch (IcatException_Exception e) {
+                        throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
+                    }
+                    serviceProvider.getFsm().queue(new DatafileInfo(dfId, name, location, df.getCreateId(), df.getModId(), dsInfo.getId()),
+                            DeferredOp.WRITE);
+                }
+
+                ByteArrayOutputStream baos = new ByteArrayOutputStream();
+                Json.createGenerator(baos).writeStartObject().write("id", dfId).write("checksum", checksum)
+                        .write("location", location.replace("\\", "\\\\").replace("'", "\\'")).write("size", size)
+                        .writeEnd().close();
+                String resp = wrap ? prefix + baos.toString() + suffix : baos.toString();
+
+                return new ValueContainer(Response.status(HttpURLConnection.HTTP_CREATED).entity(resp).build());
+
+            } catch (AlreadyLockedException e) {
+                logger.debug("Could not acquire lock, put failed");
+                throw new DataNotOnlineException("Data is busy");
+            } catch (IOException e) {
+                logger.error("I/O exception " + e.getMessage() + " putting " + name + " to Dataset with id "
+                        + datasetIdString);
+                throw new InternalException(e.getClass() + " " + e.getMessage());
+            }
+        } catch (IdsException e) {
+
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            JsonGenerator gen = Json.createGenerator(baos);
+            gen.writeStartObject().write("code", e.getClass().getSimpleName()).write("message", e.getShortMessage());
+            gen.writeEnd().close();
+            if (wrap) {
+                String pre = padding ? paddedPrefix : prefix;
+                return new ValueContainer(Response.status(e.getHttpStatusCode()).entity(pre + baos.toString().replace("'", "\\'") + suffix)
+                        .build());
+            } else {
+                return new ValueContainer(Response.status(e.getHttpStatusCode()).entity(baos.toString()).build());
+            }
+        }
+    }
+
+
+    private Long registerDatafile(String sessionId, String name, long datafileFormatId, String location, long checksum,
+                                  long size, Dataset dataset, String description, String doi, Long datafileCreateTime, Long datafileModTime)
+            throws InsufficientPrivilegesException, NotFoundException, InternalException, BadRequestException {
+
+        
+        var serviceProvider = ServiceProvider.getInstance();
+        ICAT icat = serviceProvider.getIcat();
+        
+        final Datafile df = new Datafile();
+        DatafileFormat format;
+        try {
+            format = (DatafileFormat) icat.get(sessionId, "DatafileFormat", datafileFormatId);
+        } catch (IcatException_Exception e) {
+            IcatExceptionType type = e.getFaultInfo().getType();
+            if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
+                throw new InsufficientPrivilegesException(e.getMessage());
+            }
+            if (type == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
+                throw new NotFoundException(e.getMessage());
+            }
+            throw new InternalException(type + " " + e.getMessage());
+        }
+
+        df.setDatafileFormat(format);
+        df.setLocation(location);
+        df.setFileSize(size);
+        df.setChecksum(Long.toHexString(checksum));
+        df.setName(name);
+        df.setDataset(dataset);
+        df.setDescription(description);
+        df.setDoi(doi);
+        if (datafileCreateTime != null) {
+            GregorianCalendar gregorianCalendar = new GregorianCalendar();
+            gregorianCalendar.setTimeInMillis(datafileCreateTime);
+            df.setDatafileCreateTime(datatypeFactory.newXMLGregorianCalendar(gregorianCalendar));
+        }
+        if (datafileModTime != null) {
+            GregorianCalendar gregorianCalendar = new GregorianCalendar();
+            gregorianCalendar.setTimeInMillis(datafileModTime);
+            df.setDatafileModTime(datatypeFactory.newXMLGregorianCalendar(gregorianCalendar));
+        }
+        try {
+            long dfId = icat.create(sessionId, df);
+            df.setId(dfId);
+
+            String key = serviceProvider.getPropertyHandler().getKey();
+            if (key != null) {
+                df.setLocation(location + " " + IcatSecurity.digest(dfId, location, key));
+                icat.update(sessionId, df);
+            }
+
+            logger.debug("Registered datafile for dataset {} for {}", dataset.getId(), name + " at " + location);
+            return dfId;
+        } catch (IcatException_Exception e) {
+            IcatExceptionType type = e.getFaultInfo().getType();
+            if (type == IcatExceptionType.INSUFFICIENT_PRIVILEGES || type == IcatExceptionType.SESSION) {
+                throw new InsufficientPrivilegesException(e.getMessage());
+            }
+            if (type == IcatExceptionType.VALIDATION) {
+                throw new BadRequestException(e.getMessage());
+            }
+            throw new InternalException(type + " " + e.getMessage());
+        } catch (NoSuchAlgorithmException e) {
+            throw new InternalException(e.getMessage());
+        }
+    }
+
+    public String addParametersToLogString() {
+        return "name='" + name + "' " + "datafileFormatId='"
+            + datafileFormatIdString + "' " + "datasetId='" + datasetIdString + "' " + "description='"
+            + description + "' " + "doi='" + doi + "' " + "datafileCreateTime='" + datafileCreateTimeString
+            + "' " + "datafileModTime='" + datafileModTimeString + "'";
+    }
+
+    public void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {
+        gen.write("userName", serviceProvider.getIcat().getUserName(sessionId));
+        gen.write("datafileId", dfId);
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.WRITE;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/ResetHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/ResetHandler.java
new file mode 100644
index 00000000..2fff2bb3
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/ResetHandler.java
@@ -0,0 +1,45 @@
+package org.icatproject.ids.requestHandlers;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+
+public class ResetHandler extends DataRequestHandler {
+
+    public ResetHandler(String ip, String preparedId, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.RESET, ip, preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        FiniteStateMachine fsm = ServiceProvider.getInstance().getFsm();
+        for (DataInfoBase dataInfo : dataSelectionService.getPrimaryDataInfos().values()) {
+            fsm.recordSuccess(dataInfo.getId());
+        }
+
+        return ValueContainer.getVoid();
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.MIGRATE;
+    }
+    
+
+    
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/RestoreHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/RestoreHandler.java
new file mode 100644
index 00000000..77e0c7e5
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/RestoreHandler.java
@@ -0,0 +1,35 @@
+package org.icatproject.ids.requestHandlers;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+public class RestoreHandler extends DataRequestHandler {
+
+    public RestoreHandler(String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.RESTORE, ip, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+                dataSelectionService.scheduleTasks(DeferredOp.RESTORE);
+        return ValueContainer.getVoid();
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.MIGRATE;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/WriteHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/WriteHandler.java
new file mode 100644
index 00000000..c6f994f4
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/WriteHandler.java
@@ -0,0 +1,73 @@
+package org.icatproject.ids.requestHandlers;
+
+import java.io.IOException;
+import java.util.Map;
+
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.plugin.AlreadyLockedException;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.LockManager.Lock;
+import org.icatproject.ids.services.LockManager.LockType;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+public class WriteHandler extends DataRequestHandler {
+
+    public WriteHandler(String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.WRITE, ip, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+
+        var serviceProvider = ServiceProvider.getInstance();
+
+        if (!serviceProvider.getPropertyHandler().getEnableWrite()) {
+            throw new NotImplementedException("This operation has been configured to be unavailable");
+        }
+
+        Map<Long, DataInfoBase> dsInfos = dataSelectionService.getDsInfo();
+
+        try (Lock lock = serviceProvider.getLockManager().lock(dsInfos.values(), LockType.SHARED)) {
+            if (twoLevel) {
+                boolean maybeOffline = false;
+                for (DataInfoBase dataInfo : dataSelectionService.getPrimaryDataInfos().values()) {
+                    if (!dataSelectionService.existsInMainStorage(dataInfo)) {
+                        maybeOffline = true;
+                    }
+                }
+                if (maybeOffline) {
+                    throw new DataNotOnlineException("Requested data is not online, write request refused");
+                }
+            }
+
+            dataSelectionService.scheduleTasks(DeferredOp.WRITE);
+
+        } catch (AlreadyLockedException e) {
+            logger.debug("Could not acquire lock, write failed");
+            throw new DataNotOnlineException("Data is busy");
+        } catch (IOException e) {
+            logger.error("I/O error " + e.getMessage() + " writing");
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+
+        return ValueContainer.getVoid();
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.MIGRATE;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/base/DataControllerBase.java b/src/main/java/org/icatproject/ids/requestHandlers/base/DataControllerBase.java
new file mode 100644
index 00000000..1291e98e
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/base/DataControllerBase.java
@@ -0,0 +1,65 @@
+package org.icatproject.ids.requestHandlers.base;
+
+import java.util.regex.Pattern;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+import jakarta.json.stream.JsonGenerator;
+
+public abstract class DataControllerBase {
+
+    /**
+     * matches standard UUID format of 8-4-4-4-12 hexadecimal digits
+     */
+    public static final Pattern uuidRegExp = Pattern
+            .compile("^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$");
+
+    public abstract DataSelectionService provideDataSelectionService(RequestType requestType) throws InternalException, BadRequestException, NotFoundException, InsufficientPrivilegesException, NotImplementedException;
+
+    public abstract void validateUUID() throws BadRequestException;
+
+    public abstract String addParametersToLogString();
+
+    public abstract void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException;
+
+    public abstract boolean mustZip(boolean zip, DataSelectionService dataSelectionService);
+
+    public abstract String getOperationId();
+
+    /**
+     * returns the current sessionId. If it's null or not defined it should be created
+     * @return
+     * @throws InternalException 
+     */
+    public abstract String forceGetSessionId() throws InternalException;
+
+    /**
+     * Provides a validity check for UUIDs
+     * @param thing You can give here a name of the prameter or whatever has been checked here (to provide a qualified error message if needed).
+     * @param id The String which has to be checked if it is a valid UUID
+     * @throws BadRequestException
+     */
+    public static void validateUUID(String thing, String id) throws BadRequestException {
+        if (id == null || !uuidRegExp.matcher(id).matches())
+            throw new BadRequestException("The " + thing + " parameter '" + id + "' is not a valid UUID");
+    }
+
+    protected String createSessionId() throws InternalException {
+        String sessionId;
+        try {
+            sessionId = ServiceProvider.getInstance().getIcatReader().getSessionId();
+        } catch (IcatException_Exception e) {
+            throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
+        }
+        return sessionId;
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/base/DataRequestHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/base/DataRequestHandler.java
new file mode 100644
index 00000000..72576fa5
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/base/DataRequestHandler.java
@@ -0,0 +1,80 @@
+package org.icatproject.ids.requestHandlers.base;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+import jakarta.json.stream.JsonGenerator;
+
+
+public abstract class DataRequestHandler extends RequestHandlerBase {
+
+    protected DataControllerBase dataController;
+
+    
+    protected DataRequestHandler(RequestType requestType, String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(requestType, ip);
+
+        this.dataController = new UnpreparedDataController(sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    protected DataRequestHandler(RequestType requestType, String ip, String preparedId) {
+        super(requestType, ip);
+
+        this.dataController = new PreparedDataController(preparedId);
+    }
+
+    protected DataRequestHandler(RequestType requestType, String ip, String preparedId, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(requestType, ip);
+
+        if(sessionId != null) {
+            this.dataController = new UnpreparedDataController(sessionId, investigationIds, datasetIds, datafileIds);
+        } else {
+            this.dataController = new PreparedDataController(preparedId);
+        }
+
+    }
+
+    @Override
+    protected ValueContainer handleRequest() throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        this.dataController.validateUUID();
+
+        DataSelectionService dataSelectionService = this.dataController.provideDataSelectionService(this.requestType);
+        ValueContainer result = this.handleDataRequest(dataSelectionService);
+
+        return result;
+
+    }
+
+    @Override
+    protected void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {
+        this.dataController.addParametersToTransmitterJSON(gen);
+        this.addCustomParametersToTransmitterJSON(gen);
+    }
+
+    protected abstract ValueContainer handleDataRequest(DataSelectionService dataSelectionService) throws NotImplementedException, InternalException, BadRequestException, NotFoundException, InsufficientPrivilegesException, DataNotOnlineException;
+
+    @Override
+    protected String addParametersToLogString() {
+        return this.dataController.addParametersToLogString() + " " + this.addCustomParametersToLogString();
+    }
+
+    /**
+     * Override this method in your concrete DataRequestHandler to add custom parameters to the JSON which will be transmitted.
+     * @param gen
+     */
+    protected void addCustomParametersToTransmitterJSON(JsonGenerator gen) {}
+
+    /**
+     * Override this method in your concrete DataRequestHandler to add custom parameters to the log output.
+     */
+    protected String addCustomParametersToLogString() { return "";}
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/base/PreparedDataController.java b/src/main/java/org/icatproject/ids/requestHandlers/base/PreparedDataController.java
new file mode 100644
index 00000000..f9fe6519
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/base/PreparedDataController.java
@@ -0,0 +1,84 @@
+package org.icatproject.ids.requestHandlers.base;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.NoSuchFileException;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.RequestIdNames;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.models.Prepared;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionServiceFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class PreparedDataController extends DataControllerBase {
+
+    protected final static Logger logger = LoggerFactory.getLogger(RequestHandlerBase.class);
+
+    String preparedId;
+
+    public PreparedDataController(String preparedId) {
+
+        this.preparedId = preparedId;
+    }
+
+    @Override
+    public DataSelectionService provideDataSelectionService(RequestType requestType) throws InternalException,
+            BadRequestException, NotFoundException, InsufficientPrivilegesException, NotImplementedException {
+        
+        var preparedDir = ServiceProvider.getInstance().getPropertyHandler().getCacheDir().resolve("prepared");
+
+        Prepared prepared;
+        try (InputStream stream = Files.newInputStream(preparedDir.resolve(preparedId))) {
+            prepared = Prepared.unpack(stream);
+        } catch (NoSuchFileException e) {
+            throw new NotFoundException("The preparedId " + preparedId + " is not known");
+        } catch (IOException e) {
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+
+        return DataSelectionServiceFactory.getService(prepared, requestType);
+    }
+
+    @Override
+    public void validateUUID() throws BadRequestException {
+        validateUUID(RequestIdNames.preparedId, preparedId);
+    }
+
+    @Override
+    public String addParametersToLogString() {
+        return "preparedId = '" + preparedId;
+    }
+
+    @Override
+    public void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {
+        gen.write(RequestIdNames.preparedId, this.preparedId);
+    }
+
+    @Override
+    public boolean mustZip(boolean zip, DataSelectionService dataSelectionService) {
+        return zip;
+    }
+
+    @Override
+    public String getOperationId() {
+        return this.preparedId;
+    }
+
+    @Override
+    public String forceGetSessionId() throws InternalException {
+        return this.createSessionId();
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/base/RequestHandlerBase.java b/src/main/java/org/icatproject/ids/requestHandlers/base/RequestHandlerBase.java
new file mode 100644
index 00000000..9524b7a0
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/base/RequestHandlerBase.java
@@ -0,0 +1,150 @@
+package org.icatproject.ids.requestHandlers.base;
+
+import java.io.ByteArrayOutputStream;
+import java.nio.file.Path;
+import java.util.regex.Pattern;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import jakarta.json.Json;
+import jakarta.json.stream.JsonGenerator;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.enums.StorageUnit;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.services.ServiceProvider;
+
+
+/**
+ * This base class represents all common properties and methods which are needed by each request handler.
+ * Request handlers schould be added to the internal request handler list in RequestHandlerService, to be able to be called.
+ */
+public abstract class RequestHandlerBase {
+
+    protected final static Logger logger = LoggerFactory.getLogger(RequestHandlerBase.class);
+    protected Path preparedDir;
+    protected boolean twoLevel;
+    protected StorageUnit storageUnit;
+    protected RequestType requestType;
+    protected boolean readOnly;
+    protected String ip;
+
+    /**
+     * matches standard UUID format of 8-4-4-4-12 hexadecimal digits
+     */
+    public static final Pattern uuidRegExp = Pattern
+            .compile("^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$");
+
+
+    protected RequestHandlerBase(RequestType requestType, String ip ) {
+        this.requestType = requestType;
+        this.ip = ip;
+
+        var serviceProvider = ServiceProvider.getInstance();
+        var propertyHandler = serviceProvider.getPropertyHandler();
+        this.preparedDir = propertyHandler.getCacheDir().resolve("prepared");
+        this.storageUnit = propertyHandler.getStorageUnit();
+        var archiveStorage = propertyHandler.getArchiveStorage();
+        this.twoLevel = archiveStorage != null;
+        this.readOnly = propertyHandler.getReadOnly();
+    }
+
+
+    /**
+     * Informs about the RequestType the handler ist providing a handling for.
+     * @return
+     */
+    public RequestType getRequestType() {
+        return this.requestType;
+    }
+
+    /**
+     * The core method of each request handler. It has to be overwritten in the concrete implementation to provide an individual request handling
+     * @return A ValueContainer with an indiviadual result type.
+     * @throws BadRequestException
+     * @throws InternalException
+     * @throws InsufficientPrivilegesException
+     * @throws NotFoundException
+     * @throws DataNotOnlineException
+     * @throws NotImplementedException
+     */
+    public ValueContainer handle() throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+
+        // some preprocessing
+        long start = System.currentTimeMillis();
+        logger.info("New webservice request: " + this.requestType.toString().toLowerCase() + " " + this.addParametersToLogString());
+
+        // Do it
+        ValueContainer result = this.handleRequest();
+
+        // transmitting information about the current request
+        this.transmit(start);
+
+        return result;
+
+    }
+
+
+    private void transmit(long start) throws BadRequestException {
+        if (ServiceProvider.getInstance().getLogSet().contains(this.getCallType())) {
+            try {
+                String body = this.provideTransmissionBody();
+                ServiceProvider.getInstance().getTransmitter().processMessage("archive", ip, body, start);
+            } catch (IcatException_Exception e) {
+                logger.error("Failed to prepare jms message " + e.getClass() + " " + e.getMessage());
+            }
+        }
+    }
+
+    public String provideTransmissionBody() throws BadRequestException, IcatException_Exception {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try (JsonGenerator gen = Json.createGenerator(baos).writeStartObject()) {
+            this.addParametersToTransmitterJSON(gen);
+            gen.writeEnd();
+        }
+        return baos.toString();
+    }
+
+
+    /**
+     * Override to add additional parameters to the log output for the current request
+     * @return
+     */
+    protected String addParametersToLogString() { return ""; }
+
+    /**
+     * Override to add additional parameters to the transmitter JSON
+     * @param gen
+     * @throws IcatException_Exception
+     * @throws BadRequestException
+     */
+    protected void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {}
+
+    /**
+     * The core method of each request handler. It has to be overwritten in the concrete implementation to provide an individual request handling
+     * @return A ValueContainer with an indiviadual result type.
+     * @throws BadRequestException
+     * @throws InternalException
+     * @throws InsufficientPrivilegesException
+     * @throws NotFoundException
+     * @throws DataNotOnlineException
+     * @throws NotImplementedException
+     */
+    protected abstract ValueContainer handleRequest() throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException;
+
+    /**
+     * each handler should provide its own CallType which is needed to create the Transmitter message
+     * @return the Calltype of the request
+     */
+    protected abstract CallType getCallType();
+
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/base/UnpreparedDataController.java b/src/main/java/org/icatproject/ids/requestHandlers/base/UnpreparedDataController.java
new file mode 100644
index 00000000..57668b02
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/base/UnpreparedDataController.java
@@ -0,0 +1,97 @@
+package org.icatproject.ids.requestHandlers.base;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionServiceFactory;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class UnpreparedDataController extends DataControllerBase {
+
+    public String sessionId;
+    public String investigationIds;
+    public String datasetIds;
+    public String datafileIds;
+
+    public UnpreparedDataController(String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        this.sessionId = sessionId;
+        this.investigationIds = investigationIds;
+        this.datasetIds = datasetIds;
+        this.datafileIds = datafileIds;
+    }
+
+    @Override
+    public void validateUUID() throws BadRequestException {
+        validateUUID("sessionId", sessionId);
+    }
+
+    @Override
+    public String addParametersToLogString() {
+        return "investigationIds='" + investigationIds + "' " + "datasetIds='"
+        + datasetIds + "' " + "datafileIds='" + datafileIds + "'";
+    }
+
+    @Override
+    public DataSelectionService provideDataSelectionService(RequestType requestType) throws InternalException, BadRequestException, NotFoundException, InsufficientPrivilegesException, NotImplementedException {
+        return DataSelectionServiceFactory.getService(sessionId, investigationIds, datasetIds, datafileIds, requestType);
+    }
+
+    @Override
+    public void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {
+        gen.write("userName", ServiceProvider.getInstance().getIcat().getUserName(sessionId));
+        addIds(gen, investigationIds, datasetIds, datafileIds);
+    }
+
+
+
+    protected void addIds(JsonGenerator gen, String investigationIds, String datasetIds, String datafileIds)
+            throws BadRequestException {
+        if (investigationIds != null) {
+            gen.writeStartArray("investigationIds");
+            for (long invid : DataSelectionService.getValidIds("investigationIds", investigationIds)) {
+                gen.write(invid);
+            }
+            gen.writeEnd();
+        }
+        if (datasetIds != null) {
+            gen.writeStartArray("datasetIds");
+            for (long invid : DataSelectionService.getValidIds("datasetIds", datasetIds)) {
+                gen.write(invid);
+            }
+            gen.writeEnd();
+        }
+        if (datafileIds != null) {
+            gen.writeStartArray("datafileIds");
+            for (long invid : DataSelectionService.getValidIds("datafileIds", datafileIds)) {
+                gen.write(invid);
+            }
+            gen.writeEnd();
+        }
+    }
+
+    @Override
+    public boolean mustZip(boolean zip, DataSelectionService dataSelectionService) {
+        return zip ? true : dataSelectionService.mustZip();
+    }
+
+    @Override
+    public String getOperationId() {
+        return this.sessionId;
+    }
+
+    @Override
+    public String forceGetSessionId() throws InternalException {
+        if (this.sessionId == null) {
+            this.sessionId = this.createSessionId();
+        }
+        
+        return this.sessionId;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/getSizeHandlers/GetSizeHandler.java b/src/main/java/org/icatproject/ids/requestHandlers/getSizeHandlers/GetSizeHandler.java
new file mode 100644
index 00000000..0b4aa315
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/getSizeHandlers/GetSizeHandler.java
@@ -0,0 +1,78 @@
+package org.icatproject.ids.requestHandlers.getSizeHandlers;
+
+import java.util.Map;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.requestHandlers.base.DataRequestHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+public class GetSizeHandler extends DataRequestHandler {
+
+    public GetSizeHandler(String ip, String preparedId, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.GETSIZE, ip, preparedId, sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleDataRequest(DataSelectionService dataSelectionService)
+            throws BadRequestException, InternalException, InsufficientPrivilegesException, NotFoundException,
+            DataNotOnlineException, NotImplementedException {
+        
+        logger.debug("Slow computation for normal case");
+
+        long size = 0;
+        size = this.updateSizeFromDataInfoIds(size, dataSelectionService.getDfInfo(), this.dataController.forceGetSessionId());
+
+        return new ValueContainer(size);
+    }
+
+
+    protected long updateSizeFromDataInfoIds(long size, Map<Long, DataInfoBase> dataInfos, String sessionId) throws InternalException {
+        StringBuilder sb = new StringBuilder();
+        int n = 0;
+        for (DataInfoBase dataInfo : dataInfos.values()) {
+            if (sb.length() != 0) {
+                sb.append(',');
+            }
+            sb.append(dataInfo.getId());
+            if (n++ == 500) {
+                size += getSizeFor(sessionId, sb);
+                sb = new StringBuilder();
+                n = 0;
+            }
+        }
+        if (n > 0) {
+            size += getSizeFor(sessionId, sb);
+        }
+
+        return size;
+    }
+
+
+    private long getSizeFor(String sessionId, StringBuilder sb) throws InternalException {
+        String query = "SELECT SUM(df.fileSize) from Datafile df WHERE df.id IN (" + sb.toString() + ") AND df.location IS NOT NULL";
+        try {
+            return (Long) ServiceProvider.getInstance().getIcat().search(sessionId, query).get(0);
+        } catch (IcatException_Exception e) {
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        } catch (IndexOutOfBoundsException e) {
+            return 0L;
+        }
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+    
+}
diff --git a/src/main/java/org/icatproject/ids/requestHandlers/getSizeHandlers/GetSizeHandlerForFastProcessing.java b/src/main/java/org/icatproject/ids/requestHandlers/getSizeHandlers/GetSizeHandlerForFastProcessing.java
new file mode 100644
index 00000000..6b57cd9b
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/requestHandlers/getSizeHandlers/GetSizeHandlerForFastProcessing.java
@@ -0,0 +1,127 @@
+package org.icatproject.ids.requestHandlers.getSizeHandlers;
+
+import java.util.List;
+
+import org.icatproject.Datafile;
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotFoundException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.icatproject.ids.requestHandlers.base.RequestHandlerBase;
+import org.icatproject.ids.requestHandlers.base.UnpreparedDataController;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+
+import jakarta.json.stream.JsonGenerator;
+
+public class GetSizeHandlerForFastProcessing extends RequestHandlerBase {
+
+    UnpreparedDataController dataController;
+
+    public GetSizeHandlerForFastProcessing(String ip, String sessionId, String investigationIds, String datasetIds, String datafileIds) {
+        super(RequestType.GETSIZE, ip);
+
+        this.dataController = new UnpreparedDataController(sessionId, investigationIds, datasetIds, datafileIds);
+    }
+
+    @Override
+    public ValueContainer handleRequest() throws BadRequestException, InternalException,
+            InsufficientPrivilegesException, NotFoundException, DataNotOnlineException, NotImplementedException {
+        
+        this.dataController.validateUUID();
+        var serviceProvider = ServiceProvider.getInstance();
+
+        List<Long> dfids = DataSelectionService.getValidIds("datafileIds", dataController.datafileIds);
+        List<Long> dsids = DataSelectionService.getValidIds("datasetIds", dataController.datasetIds);
+        List<Long> invids = DataSelectionService.getValidIds("investigationIds", dataController.investigationIds);
+
+        
+        if (dfids.size() + dsids.size() + invids.size() == 1) {
+
+            long size = 0;
+            size = getSizeFor(dataController.getOperationId(), invids, "df.dataset.investigation.id")
+                    + getSizeFor(dataController.getOperationId(), dsids, "df.dataset.id") 
+                    + getSizeFor(dataController.getOperationId(), dfids, "df.id");
+            logger.debug("Fast computation for simple case");
+            if (size == 0) {
+                try {
+                    if (dfids.size() != 0) {
+                        Datafile datafile = (Datafile) serviceProvider.getIcat().get(dataController.getOperationId(), "Datafile", dfids.get(0));
+                        if (datafile.getLocation() == null) {
+                            throw new NotFoundException("Datafile not found");
+                        }
+                    }
+                    if (dsids.size() != 0) {
+                        serviceProvider.getIcat().get(dataController.getOperationId(), "Dataset", dsids.get(0));
+                    }
+                    if (invids.size() != 0) {
+                        serviceProvider.getIcat().get(dataController.getOperationId(), "Investigation", invids.get(0));
+                    }
+                } catch (IcatException_Exception e) {
+                    throw new NotFoundException(e.getMessage());
+                }
+            }
+
+            return new ValueContainer(size);
+        }
+        
+        return ValueContainer.getInvalid(); //is case of fast computation is not the right way.
+
+        
+    }
+
+    @Override
+    public CallType getCallType() {
+        return CallType.INFO;
+    }
+
+    public String addParametersToLogString() { return this.dataController.addParametersToLogString(); }
+
+    public void addParametersToTransmitterJSON(JsonGenerator gen) throws IcatException_Exception, BadRequestException {
+        this.dataController.addParametersToTransmitterJSON(gen);
+    }
+
+    private long getSizeFor(String sessionId, List<Long> ids, String where) throws InternalException {
+
+        long size = 0;
+        if (ids != null) {
+
+            StringBuilder sb = new StringBuilder();
+            int n = 0;
+            for (Long id : ids) {
+                if (sb.length() != 0) {
+                    sb.append(',');
+                }
+                sb.append(id);
+                if (n++ == 500) {
+                    size += evalSizeFor(sessionId, where, sb);
+                    sb = new StringBuilder();
+                    n = 0;
+                }
+            }
+            if (n > 0) {
+                size += evalSizeFor(sessionId, where, sb);
+            }
+        }
+        return size;
+    }
+
+    private long evalSizeFor(String sessionId, String where, StringBuilder sb) throws InternalException {
+        String query = "SELECT SUM(df.fileSize) from Datafile df WHERE " + where + " IN (" + sb.toString() + ") AND df.location IS NOT NULL";
+        logger.debug("icat query for size: {}", query);
+        try {
+            return (Long) ServiceProvider.getInstance().getIcat().search(sessionId, query).get(0);
+        } catch (IcatException_Exception e) {
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        } catch (IndexOutOfBoundsException e) {
+            return 0L;
+        }
+    }
+    
+}
diff --git a/src/main/java/org/icatproject/ids/ICATGetter.java b/src/main/java/org/icatproject/ids/services/ICATGetter.java
similarity index 99%
rename from src/main/java/org/icatproject/ids/ICATGetter.java
rename to src/main/java/org/icatproject/ids/services/ICATGetter.java
index 631d153a..4073c3ce 100644
--- a/src/main/java/org/icatproject/ids/ICATGetter.java
+++ b/src/main/java/org/icatproject/ids/services/ICATGetter.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.services;
 
 import java.net.MalformedURLException;
 import java.net.URL;
diff --git a/src/main/java/org/icatproject/ids/IcatReader.java b/src/main/java/org/icatproject/ids/services/IcatReader.java
similarity index 98%
rename from src/main/java/org/icatproject/ids/IcatReader.java
rename to src/main/java/org/icatproject/ids/services/IcatReader.java
index 9245df46..9f5adbb8 100644
--- a/src/main/java/org/icatproject/ids/IcatReader.java
+++ b/src/main/java/org/icatproject/ids/services/IcatReader.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.services;
 
 import java.util.List;
 
diff --git a/src/main/java/org/icatproject/ids/LockManager.java b/src/main/java/org/icatproject/ids/services/LockManager.java
similarity index 86%
rename from src/main/java/org/icatproject/ids/LockManager.java
rename to src/main/java/org/icatproject/ids/services/LockManager.java
index c75f9ea5..c3282981 100644
--- a/src/main/java/org/icatproject/ids/LockManager.java
+++ b/src/main/java/org/icatproject/ids/services/LockManager.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.services;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -11,9 +11,10 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
 import org.icatproject.ids.plugin.AlreadyLockedException;
-import org.icatproject.ids.plugin.DsInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
 
 @Singleton
@@ -130,7 +131,7 @@ private void init() {
         logger.debug("LockManager initialized.");
     }
 
-    public Lock lock(DsInfo ds, LockType type) throws AlreadyLockedException, IOException {
+    public Lock lock(DatasetInfo ds, LockType type) throws AlreadyLockedException, IOException {
         Long id = ds.getDsId();
         assert id != null;
         synchronized (lockMap) {
@@ -150,10 +151,12 @@ public Lock lock(DsInfo ds, LockType type) throws AlreadyLockedException, IOExce
         }
     }
 
-    public Lock lock(Collection<DsInfo> datasets, LockType type) throws AlreadyLockedException, IOException {
+    public Lock lock(Collection<DataInfoBase> datasets, LockType type) throws AlreadyLockedException, IOException, InternalException {
         LockCollection locks = new LockCollection();
         try {
-            for (DsInfo ds : datasets) {
+            for (DataInfoBase dataInfo : datasets) {
+                DatasetInfo ds = (DatasetInfo) dataInfo;
+                if(ds == null) throw new InternalException("Could not cast " + dataInfo.getClass() + " to DataSetInfo. Did you handed over another sub type of DataInfoBase? ");
                 locks.add(lock(ds, type));
             }
         } catch (AlreadyLockedException | IOException e) {
diff --git a/src/main/java/org/icatproject/ids/PropertyHandler.java b/src/main/java/org/icatproject/ids/services/PropertyHandler.java
similarity index 98%
rename from src/main/java/org/icatproject/ids/PropertyHandler.java
rename to src/main/java/org/icatproject/ids/services/PropertyHandler.java
index a82c846d..e3cbe354 100644
--- a/src/main/java/org/icatproject/ids/PropertyHandler.java
+++ b/src/main/java/org/icatproject/ids/services/PropertyHandler.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.services;
 
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
@@ -22,7 +22,8 @@
 
 import org.icatproject.ICAT;
 import org.icatproject.IcatException_Exception;
-import org.icatproject.ids.IdsBean.CallType;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.enums.StorageUnit;
 import org.icatproject.ids.plugin.ArchiveStorageInterface;
 import org.icatproject.ids.plugin.MainStorageInterface;
 import org.icatproject.ids.plugin.ZipMapperInterface;
@@ -345,7 +346,7 @@ public long getStopArchivingLevel() {
         return stopArchivingLevel;
     }
 
-    StorageUnit getStorageUnit() {
+    public StorageUnit getStorageUnit() {
         return storageUnit;
     }
 
diff --git a/src/main/java/org/icatproject/ids/services/ServiceProvider.java b/src/main/java/org/icatproject/ids/services/ServiceProvider.java
new file mode 100644
index 00000000..dc179ad5
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/services/ServiceProvider.java
@@ -0,0 +1,91 @@
+package org.icatproject.ids.services;
+
+import java.util.Set;
+
+import org.icatproject.ICAT;
+import org.icatproject.ids.enums.CallType;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.plugin.MainStorageInterface;
+
+/**
+ * This class provides multiple services to the developer
+ * Maybe it is just for the redesign for version 3 and will later be replaced with dependency injection, when it will be more clear where which service is used.
+ */
+public class ServiceProvider {
+
+    private static ServiceProvider instance = null;
+
+    private Transmitter transmitter;
+    private FiniteStateMachine fsm;
+    private LockManager lockManager;
+    private IcatReader icatReader;
+    private PropertyHandler propertyHandler;
+
+    private ServiceProvider(PropertyHandler propertyHandler, Transmitter transmitter, FiniteStateMachine fsm, LockManager lockManager, IcatReader reader) {
+        this.transmitter = transmitter;
+        this.fsm = fsm;
+        this.lockManager = lockManager;
+        this.icatReader = reader;
+        this.propertyHandler = propertyHandler;
+    }
+
+    /**
+     * At first, the ServiceProvider has to be created. Do not call getInstance() before you have called createInstande()
+     * @param transmitter
+     * @param fsm
+     * @param lockManager
+     * @param reader
+     */
+    public static void createInstance(Transmitter transmitter, FiniteStateMachine fsm, LockManager lockManager, IcatReader reader) {
+
+        createInstance(PropertyHandler.getInstance(), transmitter, fsm, lockManager, reader);
+    }
+
+    public static void createInstance(PropertyHandler propertyHandler, Transmitter transmitter, FiniteStateMachine fsm, LockManager lockManager, IcatReader reader) {
+
+        if(instance != null) return;
+
+        instance = new ServiceProvider(propertyHandler, transmitter, fsm, lockManager, reader);
+    }
+
+    public static ServiceProvider getInstance() {
+        if(instance == null) {
+            throw new RuntimeException("ServiceProvider is not yet instantiated, please call createInstance at first.");
+        }
+        return instance;
+    }
+
+    public Transmitter getTransmitter() {
+        return transmitter;
+    }
+
+    public FiniteStateMachine getFsm() {
+        return fsm;
+    }
+
+    public LockManager getLockManager() {
+        return lockManager;
+    }
+
+    public IcatReader getIcatReader() {
+        return icatReader;
+    }
+
+    public PropertyHandler getPropertyHandler() {
+        return this.propertyHandler;
+    }
+
+    public MainStorageInterface getMainStorage() {
+        return this.getPropertyHandler().getMainStorage();
+    }
+
+    public ICAT getIcat() {
+        return this.getPropertyHandler().getIcatService();
+    }
+
+    public Set<CallType> getLogSet() {
+        return PropertyHandler.getInstance().getLogSet();
+    }
+
+
+}
diff --git a/src/main/java/org/icatproject/ids/Transmitter.java b/src/main/java/org/icatproject/ids/services/Transmitter.java
similarity index 98%
rename from src/main/java/org/icatproject/ids/Transmitter.java
rename to src/main/java/org/icatproject/ids/services/Transmitter.java
index 1e3c36d4..996522cb 100644
--- a/src/main/java/org/icatproject/ids/Transmitter.java
+++ b/src/main/java/org/icatproject/ids/services/Transmitter.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.services;
 
 import javax.naming.InitialContext;
 import javax.naming.NamingException;
diff --git a/src/main/java/org/icatproject/ids/services/UnfinishedWorkService.java b/src/main/java/org/icatproject/ids/services/UnfinishedWorkService.java
new file mode 100644
index 00000000..5f9b372b
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/services/UnfinishedWorkService.java
@@ -0,0 +1,120 @@
+package org.icatproject.ids.services;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.icatproject.Datafile;
+import org.icatproject.Dataset;
+import org.icatproject.IcatExceptionType;
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.StorageUnit;
+import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.helpers.LocationHelper;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This class is to handle not finished work.
+ * It could be redesigned with sub classes depending on StorageUnit, but it isn't worth it i guess, just for one abstract method (loadDataInfo()).
+ */
+public class UnfinishedWorkService {
+
+
+    protected final static Logger logger = LoggerFactory.getLogger(UnfinishedWorkService.class);
+
+    public UnfinishedWorkService() {
+        
+    }
+
+    public void restartUnfinishedWork(Path markerDir, String key) throws InternalException {
+
+        try {
+            var serviceProvider = ServiceProvider.getInstance();
+            StorageUnit storageUnit = serviceProvider.getPropertyHandler().getStorageUnit();
+
+            for (File file : markerDir.toFile().listFiles()) {
+
+                if(storageUnit == null) break;
+                
+                long id = Long.parseLong(file.toPath().getFileName().toString());
+                try {
+                    DataInfoBase dataInfo = this.loadDataInfo(storageUnit, id);
+                    serviceProvider.getFsm().queue(dataInfo, DeferredOp.WRITE);
+                    logger.info("Queued " + storageUnit.toString().toLowerCase() + " with id " + id + " " + dataInfo
+                            + " to be written as it was not written out previously by IDS");
+                } catch (IcatException_Exception e) {
+                    if (e.getFaultInfo().getType() == IcatExceptionType.NO_SUCH_OBJECT_FOUND) {
+                        logger.warn( storageUnit.toString().toLowerCase() + " with id " + id
+                                + " was not written out by IDS and now no longer known to ICAT");
+                        Files.delete(file.toPath());
+                    } else {
+                        throw e;
+                    }
+                }
+            }
+        } catch (Exception e) {
+            throw new InternalException(e.getClass() + " " + e.getMessage());
+        }
+    }
+
+
+    public void cleanPreparedDir(Path preparedDir) {
+        for (File file : preparedDir.toFile().listFiles()) {
+            Path path = file.toPath();
+            String pf = path.getFileName().toString();
+            if (pf.startsWith("tmp.") || pf.endsWith(".tmp")) {
+                try {
+                    long thisSize = 0;
+                    if (Files.isDirectory(path)) {
+                        for (File notZipFile : file.listFiles()) {
+                            thisSize += Files.size(notZipFile.toPath());
+                            Files.delete(notZipFile.toPath());
+                        }
+                    }
+                    thisSize += Files.size(path);
+                    Files.delete(path);
+                    logger.debug("Deleted " + path + " to reclaim " + thisSize + " bytes");
+                } catch (IOException e) {
+                    logger.debug("Failed to delete " + path + e.getMessage());
+                }
+            }
+        }
+    }
+
+
+    public void cleanDatasetCache(Path datasetDir) {
+        for (File dsFile : datasetDir.toFile().listFiles()) {
+            Path path = dsFile.toPath();
+            try {
+                long thisSize = Files.size(path);
+                Files.delete(path);
+                logger.debug("Deleted " + path + " to reclaim " + thisSize + " bytes");
+            } catch (IOException e) {
+                logger.debug("Failed to delete " + path + " " + e.getClass() + " " + e.getMessage());
+            }
+        }
+    }
+
+
+    private DataInfoBase loadDataInfo(StorageUnit storageUnit, long id) throws IcatException_Exception, InsufficientPrivilegesException, InternalException {
+        if(storageUnit == StorageUnit.DATASET) {
+            Dataset ds = (Dataset) ServiceProvider.getInstance().getIcatReader().get("Dataset ds INCLUDE ds.investigation.facility", id);
+            return new DatasetInfo(ds);
+        }
+
+        if(storageUnit == StorageUnit.DATAFILE) {
+            Datafile df = (Datafile) ServiceProvider.getInstance().getIcatReader().get("Datafile ds INCLUDE ds.dataset", id);
+            String location = LocationHelper.getLocation(df.getId(), df.getLocation());
+            return new DatafileInfo(id, df.getName(), location, df.getCreateId(), df.getModId(), df.getDataset().getId());
+        }
+
+        return null;
+    }
+}
diff --git a/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionService.java b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionService.java
new file mode 100644
index 00000000..650e410f
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionService.java
@@ -0,0 +1,289 @@
+package org.icatproject.ids.services.dataSelectionService;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.OptionalLong;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.locks.ReentrantLock;
+
+import org.icatproject.IcatException_Exception;
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.exceptions.DataNotOnlineException;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DataSelection;
+import org.icatproject.ids.services.ServiceProvider;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public abstract class DataSelectionService {
+
+    protected final static Logger logger = LoggerFactory.getLogger(DataSelectionService.class);
+
+    protected DataSelection dataSelection;
+    protected RequestType requestType;
+
+
+    protected static ExecutorService threadPool;
+    static { threadPool = Executors.newCachedThreadPool(); }
+
+    private Map<String, PreparedStatus> preparedStatusMap = new ConcurrentHashMap<>();
+
+    class PreparedStatus {
+        public ReentrantLock lock = new ReentrantLock();
+        public Long fromElement;
+        public Future<?> future;
+
+    }
+
+    protected DataSelectionService(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos, Set<Long> emptyDatasets, 
+        List<Long> invids2, List<Long> dsids, List<Long> dfids, long length, Boolean zip, Boolean compress, RequestType requestType) {
+
+        this.dataSelection = new DataSelection(dsInfos, dfInfos, emptyDatasets, invids2, dsids, dfids, length, zip, compress);
+
+        this.requestType = requestType;
+    }
+
+    public abstract boolean isPrepared(String preparedId) throws InternalException;
+
+    /**
+     * To get the DataInfos that is currently worked with, depending on StorageUnit
+     * @return
+     */
+    public abstract SortedMap<Long, DataInfoBase> getPrimaryDataInfos();
+
+    public abstract boolean existsInMainStorage(DataInfoBase dataInfo) throws InternalException;
+
+    public abstract void queueDelete() throws NotImplementedException, InternalException;
+
+    public abstract void scheduleTasks(DeferredOp operation) throws NotImplementedException, InternalException;
+
+    //TODO: maybe implementing this method here whould be the better way, than making it abstract. But we will miss the NotImplementedException for SingleLevelStorage in that case.
+    // should we change the tests and the behavior of the ids server here
+    // public void scheduleTasks(DeferredOp operation) throws NotImplementedException, InternalException {
+    //     for (DataInfoBase dataInfo : this.getPrimaryDataInfos().values()) {      // in case of SingleLevelStorage an empty map is returned and nothing will happen (even not an exception).
+    //         ServiceProvider.getInstance().getFsm().queue(dataInfo, operation);
+    //     }
+    // }
+
+    public SortedMap<Long, DataInfoBase> getDsInfo() {
+        return this.dataSelection.getDsInfo();
+    }
+
+
+    public SortedMap<Long, DataInfoBase> getDfInfo() {
+        return this.dataSelection.getDfInfo();
+    }
+
+    public Boolean getZip() {
+        return this.dataSelection.getZip();
+    }
+
+    public Boolean getCompress() {
+        return this.dataSelection.getCompress();
+    }
+
+    public long getLength() {
+        return this.dataSelection.getLength();
+    }
+
+
+    public boolean mustZip() {
+        return this.dataSelection.mustZip();
+    }
+
+    public boolean isSingleDataset() {
+        return this.dataSelection.isSingleDataset();
+    }
+
+
+    public Set<Long> getEmptyDatasets() {
+        return this.dataSelection.getEmptyDatasets();
+    }
+
+
+    /**
+     * tries to extract a list of ids from a comma separated id string. No spaces or leading 0's. Also
+     * accepts null.
+     * @param thing the name of the id list - for better error message
+     * @param idList a String which shoald contain long numbers seperated by commas
+     * @return list of long numbers - the extracted id values
+     * @throws BadRequestException
+     */
+    public static List<Long> getValidIds(String thing, String idList) throws BadRequestException {
+
+        List<Long> result;
+        if (idList == null) {
+            result = Collections.emptyList();
+        } else {
+            String[] ids = idList.split("\\s*,\\s*");
+            result = new ArrayList<>(ids.length);
+            for (String id : ids) {
+                try {
+                    result.add(Long.parseLong(id));
+                } catch (NumberFormatException e) {
+                    throw new BadRequestException("The " + thing + " parameter '" + idList + "' is not a valid "
+                            + "string representation of a comma separated list of longs");
+                }
+            }
+        }
+        return result;
+    }
+
+
+    private boolean restoreIfOffline(DataInfoBase dataInfo) throws InternalException {
+        boolean maybeOffline = false;
+        var serviceProvider = ServiceProvider.getInstance();
+        if (serviceProvider.getFsm().getMaybeOffline().contains(dataInfo)) {
+            maybeOffline = true;
+        } else if (!this.existsInMainStorage(dataInfo)) {
+            serviceProvider.getFsm().queue(dataInfo, DeferredOp.RESTORE);
+            maybeOffline = true;
+        }
+        return maybeOffline;
+    }
+
+
+    public void checkOnline()throws InternalException, DataNotOnlineException {
+
+        boolean maybeOffline = false;
+        for (DataInfoBase dfInfo : this.getPrimaryDataInfos().values()) {
+            if (this.restoreIfOffline(dfInfo)) {
+                maybeOffline = true;
+            }
+        }
+        if (maybeOffline) {
+            throw new DataNotOnlineException(
+                    "Before getting, putting, etc.  a datafile or dataset, it must be restored, restoration requested automatically");
+        }
+    }
+
+
+    public void restoreDataInfos() {
+
+        var dataInfos = this.getPrimaryDataInfos().values();
+        if(!dataInfos.isEmpty()) {
+            for (DataInfoBase dataInfo : dataInfos) {
+                ServiceProvider.getInstance().getFsm().recordSuccess(dataInfo.getId());
+            }
+            threadPool.submit(new RestoreDataInfoTask(dataInfos, this, false));
+        }
+    }
+
+
+    public OptionalLong getFileLength() {
+        if (this.dataSelection.getDfInfo().isEmpty() || this.dataSelection.mustZip()) {
+            return OptionalLong.empty();
+        }
+
+        return OptionalLong.of(this.dataSelection.getLength());
+    }
+
+
+    protected boolean areDataInfosPrepared(String preparedId) throws InternalException {
+        boolean prepared = true;
+        var serviceProvider = ServiceProvider.getInstance();
+        PreparedStatus status = preparedStatusMap.computeIfAbsent(preparedId, k -> new PreparedStatus());
+
+        Collection<DataInfoBase> toCheck = status.fromElement == null ? this.getPrimaryDataInfos().values()
+                        : this.getPrimaryDataInfos().tailMap(status.fromElement).values();
+        logger.debug("Will check online status of {} entries", toCheck.size());
+        for (DataInfoBase dataInfo : toCheck) {
+            serviceProvider.getFsm().checkFailure(dataInfo.getId());
+            if (this.restoreIfOffline(dataInfo)) {
+                prepared = false;
+                status.fromElement = dataInfo.getId();
+                toCheck = this.getPrimaryDataInfos().tailMap(status.fromElement).values();
+                logger.debug("Will check in background status of {} entries", toCheck.size());
+                status.future = threadPool.submit(new RestoreDataInfoTask(toCheck, this, true));
+                break;
+            }
+        }
+        if (prepared) {
+            toCheck = status.fromElement == null ? Collections.emptySet()
+                    : this.getPrimaryDataInfos().headMap(status.fromElement).values();
+            logger.debug("Will check finally online status of {} entries", toCheck.size());
+            for (DataInfoBase dataInfo : toCheck) {
+                serviceProvider.getFsm().checkFailure(dataInfo.getId());
+                if (this.restoreIfOffline(dataInfo)) {
+                    prepared = false;
+                }
+            }
+        }
+
+        return prepared;
+    }
+
+
+    public void delete() throws InternalException, NotImplementedException {
+
+        var serviceProvider = ServiceProvider.getInstance();
+
+        /*
+         * Delete the local copy directly rather than queueing it as it has
+         * been removed from ICAT so will not be accessible to any
+         * subsequent IDS calls.
+         */
+        for (DataInfoBase dataInfo : this.dataSelection.getDfInfo().values()) {
+            var dfInfo = (DatafileInfo) dataInfo;
+            String location = dataInfo.getLocation();
+            try {
+                if ((long) serviceProvider.getIcatReader()
+                        .search("SELECT COUNT(df) FROM Datafile df WHERE df.location LIKE '" + location.replaceAll("'", "''") + "%'")
+                        .get(0) == 0) {
+                    if (serviceProvider.getMainStorage().exists(location)) {
+                        logger.debug("Delete physical file " + location + " from main storage");
+                        serviceProvider.getMainStorage().delete(location, dfInfo.getCreateId(), dfInfo.getModId());
+                    }
+                }
+            } catch (IcatException_Exception e) {
+                throw new InternalException(e.getFaultInfo().getType() + " " + e.getMessage());
+            } catch (IOException e) {
+                logger.error("I/O error " + e.getMessage() + " deleting " + dfInfo);
+                throw new InternalException(e.getClass() + " " + e.getMessage());
+            }
+        }
+
+        this.queueDelete();
+    }
+
+
+    private class RestoreDataInfoTask implements Callable<Void> {
+
+        private Collection<DataInfoBase> dataInfos;
+        private DataSelectionService dataselection;
+        private boolean checkFailure;
+
+        public RestoreDataInfoTask(Collection<DataInfoBase> dataInfos, DataSelectionService dataSelection, boolean checkFailure) {
+            this.dataInfos = dataInfos;
+            this.dataselection = dataSelection;
+            this.checkFailure = checkFailure;
+        }
+
+        @Override
+        public Void call() throws Exception {
+            for (DataInfoBase dataInfo : dataInfos) {
+                if(checkFailure)
+                    ServiceProvider.getInstance().getFsm().checkFailure(dataInfo.getId());
+                dataselection.restoreIfOffline(dataInfo);
+            }
+            return null;
+        }
+        
+    }
+
+}
diff --git a/src/main/java/org/icatproject/ids/DataSelection.java b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceFactory.java
similarity index 50%
rename from src/main/java/org/icatproject/ids/DataSelection.java
rename to src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceFactory.java
index 0a901edd..25ff3ccb 100644
--- a/src/main/java/org/icatproject/ids/DataSelection.java
+++ b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceFactory.java
@@ -1,4 +1,4 @@
-package org.icatproject.ids;
+package org.icatproject.ids.services.dataSelectionService;
 
 import java.io.ByteArrayInputStream;
 import java.util.ArrayList;
@@ -7,15 +7,9 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.OptionalLong;
 import java.util.Set;
-
-import jakarta.json.Json;
-import jakarta.json.JsonArray;
-import jakarta.json.JsonValue;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import java.util.SortedMap;
+import java.util.TreeMap;
 
 import org.icatproject.Datafile;
 import org.icatproject.Dataset;
@@ -24,109 +18,183 @@
 import org.icatproject.IcatException_Exception;
 import org.icatproject.icat.client.IcatException;
 import org.icatproject.icat.client.Session;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.enums.StorageUnit;
 import org.icatproject.ids.exceptions.BadRequestException;
 import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
 import org.icatproject.ids.exceptions.InternalException;
 import org.icatproject.ids.exceptions.NotFoundException;
-import org.icatproject.ids.plugin.DsInfo;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.helpers.LocationHelper;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.models.Prepared;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import jakarta.json.Json;
+import jakarta.json.JsonArray;
+import jakarta.json.JsonValue;
+
+public class DataSelectionServiceFactory {
 
-/**
- * Class to convert 3 comma separated strings containing Investigation,
- * Dataset and Datafile IDs into a Map of DsInfo objects and a Set of
- * DfInfo objects, containing all the fields required to perform many
- * of the core IDS operations.
- */
-public class DataSelection {
+    private final static Logger logger = LoggerFactory.getLogger(DataSelectionServiceFactory.class);
 
-    private final static Logger logger = LoggerFactory.getLogger(DataSelection.class);
+    private static DataSelectionServiceFactory instance = null;
 
+    private PropertyHandler propertyHandler;
     private ICAT icat;
+    private IcatReader icatReader;
     private org.icatproject.icat.client.ICAT restIcat;
-    private String userSessionId;
-    private Session userRestSession;
-    private Session restSessionToUse;
     private int maxEntities;
-    private List<Long> invids;
-    private List<Long> dsids;
-    private List<Long> dfids;
-    private Map<Long, DsInfo> dsInfos;
-    private Set<DfInfoImpl> dfInfos;
-    private Set<Long> emptyDatasets;
-    private boolean dsWanted;
-    private boolean dfWanted;
-    private long length;
-
+    private HashMap<RequestType, Returns> requestTypeToReturnsMapping;
 
     public enum Returns {
         DATASETS, DATASETS_AND_DATAFILES, DATAFILES
     }
 
-    public DataSelection(PropertyHandler propertyHandler, IcatReader icatReader, String userSessionId,
-                         String investigationIds, String datasetIds, String datafileIds, Returns returns)
-            throws BadRequestException, NotFoundException, InsufficientPrivilegesException, InternalException {
+    public static DataSelectionServiceFactory getInstance() throws InternalException {
+        if (instance == null) {
+            var serviceProvider = ServiceProvider.getInstance();
+            instance = new DataSelectionServiceFactory(serviceProvider.getPropertyHandler(), serviceProvider.getIcatReader());
+        }
+        return instance;
+    }
 
-        dfids = getValidIds("datafileIds", datafileIds);
-        dsids = getValidIds("datasetIds", datasetIds);
-        invids = getValidIds("investigationIds", investigationIds);
-        dfWanted = returns == Returns.DATASETS_AND_DATAFILES || returns == Returns.DATAFILES;
-        dsWanted = returns == Returns.DATASETS_AND_DATAFILES || returns == Returns.DATASETS;
+    public static DataSelectionServiceFactory getInstanceOnlyForTesting(PropertyHandler propertyHandler, IcatReader reader) throws InternalException {
+        if (instance == null) {
+            instance = new DataSelectionServiceFactory(propertyHandler, reader);
+        }
+        return instance;
+    }
+
+    public static DataSelectionService getService(String userSessionId, String investigationIds, String datasetIds, String datafileIds, RequestType requestType) 
+                                            throws InternalException, BadRequestException, NotFoundException, InsufficientPrivilegesException, NotImplementedException {
+
+        return DataSelectionServiceFactory.getInstance().getSelectionService(userSessionId, investigationIds, datasetIds, datafileIds, requestType);
+    }
 
+
+    /**
+     * created a DataSelectionBase object from already created data infos. That's why no infos must be loaded from ICAT.
+     * @param dsInfos
+     * @param dfInfos
+     * @param emptyDatasets
+     * @param fileLength
+     * @param requestType
+     * @return
+     * @throws InternalException
+     */
+    public static DataSelectionService getService(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos, Set<Long> emptyDatasets, long fileLength, RequestType requestType) throws InternalException {
+
+        var prepared = new Prepared(dsInfos, dfInfos, emptyDatasets, fileLength);
+        return DataSelectionServiceFactory.getService(prepared, requestType);
+    }
+
+    public static DataSelectionService getService(Prepared prepared, RequestType requestType) throws InternalException {
+        List<Long> dsids = new ArrayList<Long>(prepared.dsInfos.keySet());
+        List<Long> dfids = new ArrayList<Long>();
+        List<Long> invIds = new ArrayList<Long>();
+        var dataFileInfos = new HashMap<Long, DataInfoBase>();
+        for(DataInfoBase dfInfo: prepared.dfInfos.values()) {
+            dfids.add(dfInfo.getId());
+            dataFileInfos.put(dfInfo.getId(), dfInfo);
+            dfids.add(dfInfo.getId());
+        }
+
+        for(DataInfoBase dsInfo : prepared.dsInfos.values()) {
+            dsids.add(dsInfo.getId());
+            invIds.add( ((DatasetInfo)dsInfo).getInvId() );
+        }
+
+        return DataSelectionServiceFactory.getInstance().createSelectionService(prepared.dsInfos, prepared.dfInfos, prepared.emptyDatasets, invIds, dsids, dfids, prepared.fileLength, prepared.zip, prepared.compress, requestType);
+    }
+
+    private DataSelectionServiceFactory(PropertyHandler propertyHandler, IcatReader reader) throws InternalException
+    {
+        logger.info("### Constructing...");
+        this.propertyHandler = propertyHandler;
         this.icat = propertyHandler.getIcatService();
+        this.icatReader = reader;
         this.restIcat = propertyHandler.getRestIcat();
-        maxEntities = propertyHandler.getMaxEntities();
-        this.userSessionId = userSessionId;
-        userRestSession = restIcat.getSession(userSessionId);
+        this.maxEntities = propertyHandler.getMaxEntities();
+
+        this.createRequestTypeToReturnsMapping();
+
+        logger.info("### Constructing finished");
+    }
+
+    private DataSelectionService createSelectionService(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos, 
+                                        Set<Long> emptyDatasets, List<Long> invids, List<Long> dsids,
+                                        List<Long> dfids, long length, Boolean zip, Boolean compress, 
+                                        RequestType requestType) throws InternalException {
+
+        StorageUnit storageUnit = this.propertyHandler.getStorageUnit();
+
+        if(storageUnit == null )
+            return new DataSelectionServiceForSingleLevelStorage(dsInfos, dfInfos, emptyDatasets, invids, dsids, dfids, length, zip, compress, requestType);
+
+        else if (storageUnit == StorageUnit.DATAFILE)
+            return new DataSelectionServiceForStorageUnitDatafile(dsInfos, dfInfos, emptyDatasets, invids, dsids, dfids, length, zip, compress, requestType);
+
+        else if(storageUnit == StorageUnit.DATASET)
+            return new DataSelectionServiceForStorageUnitDataset(dsInfos, dfInfos, emptyDatasets, invids, dsids, dfids, length, zip, compress, requestType);
+
+        else throw new InternalException("StorageUnit " + storageUnit + " unknown. Maybe you forgot to handle a new StorageUnit here?");
+
+    }
+
+    public DataSelectionService getSelectionService( String userSessionId, String investigationIds, String datasetIds, String datafileIds, RequestType requestType) 
+                                    throws InternalException, BadRequestException, NotFoundException, InsufficientPrivilegesException, NotImplementedException {
+        
+        List<Long> dfids = getValidIds("datafileIds", datafileIds);
+        List<Long> dsids = getValidIds("datasetIds", datasetIds);
+        List<Long> invids = getValidIds("investigationIds", investigationIds);
+
+        Returns returns = this.getReturns(requestType);
+        boolean dfWanted = returns == Returns.DATASETS_AND_DATAFILES || returns == Returns.DATAFILES;
+        boolean dsWanted = returns == Returns.DATASETS_AND_DATAFILES || returns == Returns.DATASETS;
+
+        Session userRestSession = restIcat.getSession(userSessionId);
         // by default use the user's REST ICAT session
-        restSessionToUse = userRestSession;
+        Session restSessionToUse = userRestSession;
+        
         try {
             logger.debug("useReaderForPerformance = {}", propertyHandler.getUseReaderForPerformance());
             if (propertyHandler.getUseReaderForPerformance()) {
                 // if this is set, use a REST session for the reader account where possible
                 // to improve performance due to the final database queries being simpler
-                restSessionToUse = restIcat.getSession(icatReader.getSessionId());
+                restSessionToUse = restIcat.getSession(this.icatReader.getSessionId());
             }
         } catch (IcatException_Exception e) {
             throw new InternalException(e.getClass() + " " + e.getMessage());
         }
 
         logger.debug("dfids: {} dsids: {} invids: {}", dfids, dsids, invids);
-        resolveDatasetIds();
-    }
-
-    /**
-     * Checks to see if the investigation, dataset or datafile id list is a
-     * valid comma separated list of longs. No spaces or leading 0's. Also
-     * accepts null.
-     */
-    public static List<Long> getValidIds(String thing, String idList) throws BadRequestException {
 
-        List<Long> result;
-        if (idList == null) {
-            result = Collections.emptyList();
-        } else {
-            String[] ids = idList.split("\\s*,\\s*");
-            result = new ArrayList<>(ids.length);
-            for (String id : ids) {
-                try {
-                    result.add(Long.parseLong(id));
-                } catch (NumberFormatException e) {
-                    throw new BadRequestException("The " + thing + " parameter '" + idList + "' is not a valid "
-                            + "string representation of a comma separated list of longs");
-                }
-            }
-        }
-        return result;
+        return prepareFromIds(dfWanted, dsWanted, dfids, dsids, invids, userSessionId, restSessionToUse, userRestSession, requestType);
     }
 
-    private void resolveDatasetIds()
+    
+
+    private DataSelectionService prepareFromIds(boolean dfWanted, boolean dsWanted, List<Long> dfids, List<Long> dsids, List<Long> invids, String userSessionId, Session restSessionToUse, Session userRestSession, RequestType requestType)
             throws NotFoundException, InsufficientPrivilegesException, InternalException, BadRequestException {
-        dsInfos = new HashMap<>();
-        emptyDatasets = new HashSet<>();
-        if (dfWanted) {
-            dfInfos = new HashSet<>();
+        var dsInfos = new TreeMap<Long, DataInfoBase>();
+        var emptyDatasets = new HashSet<Long>();
+        var dfInfos = new TreeMap<Long, DataInfoBase>();
+
+        long length = 0;
+
+        if (dfWanted) { //redundant ?
+            dfInfos = new TreeMap<Long, DataInfoBase>();
         }
 
         try {
+
             for (Long dfid : dfids) {
                 List<Object> dss = icat.search(userSessionId,
                         "SELECT ds FROM Dataset ds JOIN ds.datafiles df WHERE df.id = " + dfid
@@ -134,13 +202,13 @@ private void resolveDatasetIds()
                 if (dss.size() == 1) {
                     Dataset ds = (Dataset) dss.get(0);
                     long dsid = ds.getId();
-                    dsInfos.put(dsid, new DsInfoImpl(ds));
+                    dsInfos.put(dsid, new DatasetInfo(ds));
                     if (dfWanted) {
                         Datafile df = (Datafile) icat.get(userSessionId, "Datafile", dfid);
                         length += df.getFileSize();
-                        String location = IdsBean.getLocation(dfid, df.getLocation());
-                        dfInfos.add(
-                                new DfInfoImpl(dfid, df.getName(), location, df.getCreateId(), df.getModId(), dsid));
+                        String location = LocationHelper.getLocation(dfid, df.getLocation());
+                        dfInfos.put( df.getId(),
+                                new DatafileInfo(dfid, df.getName(), location, df.getCreateId(), df.getModId(), dsid));
                     }
                 } else {
                     // Next line may reveal a permissions problem
@@ -151,7 +219,7 @@ private void resolveDatasetIds()
 
             for (Long dsid : dsids) {
                 Dataset ds = (Dataset) icat.get(userSessionId, "Dataset ds INCLUDE ds.investigation.facility", dsid);
-                dsInfos.put(dsid, new DsInfoImpl(ds));
+                dsInfos.put(dsid, new DatasetInfo(ds));
                 // dataset access for the user has been checked so the REST session for the
                 // reader account can be used if the IDS setting to allow this is enabled
                 String query = "SELECT min(df.id), max(df.id), count(df.id) FROM Datafile df WHERE df.dataset.id = "
@@ -161,7 +229,7 @@ private void resolveDatasetIds()
                 if (result.getJsonNumber(2).longValueExact() == 0) { // Count 0
                     emptyDatasets.add(dsid);
                 } else if (dfWanted) {
-                    manyDfs(dsid, result);
+                    manyDfs(dfInfos, dsid, restSessionToUse, result);
                 }
             }
 
@@ -170,7 +238,7 @@ private void resolveDatasetIds()
                         + invid;
                 JsonArray result = Json.createReader(new ByteArrayInputStream(userRestSession.search(query).getBytes()))
                         .readArray().getJsonArray(0);
-                manyDss(invid, result);
+                manyDss(dsInfos, emptyDatasets, dfInfos, invid, dfWanted, userRestSession, restSessionToUse, result);
 
             }
 
@@ -196,16 +264,80 @@ private void resolveDatasetIds()
             }
         }
         /*
-         * TODO don't calculate what is not needed - however this ensures that
+         * TODO: don't calculate what is not needed - however this ensures that
          * the flag is respected
          */
         if (!dsWanted) {
             dsInfos = null;
             emptyDatasets = null;
         }
+
+        return this.createSelectionService(dsInfos, dfInfos, emptyDatasets, invids, dsids, dfids, length, false, false, requestType);
     }
+    
+
+    /**
+     * Checks to see if the investigation, dataset or datafile id list is a
+     * valid comma separated list of longs. No spaces or leading 0's. Also
+     * accepts null.
+     */
+    public static List<Long> getValidIds(String thing, String idList) throws BadRequestException {
 
-    private void manyDss(Long invid, JsonArray result)
+        List<Long> result;
+        if (idList == null) {
+            result = Collections.emptyList();
+        } else {
+            String[] ids = idList.split("\\s*,\\s*");
+            result = new ArrayList<>(ids.length);
+            for (String id : ids) {
+                try {
+                    result.add(Long.parseLong(id));
+                } catch (NumberFormatException e) {
+                    throw new BadRequestException("The " + thing + " parameter '" + idList + "' is not a valid "
+                            + "string representation of a comma separated list of longs");
+                }
+            }
+        }
+        return result;
+    }
+
+    private void manyDfs(Map<Long, DataInfoBase> dfInfos, long dsid, Session restSessionToUse, JsonArray result)
+            throws IcatException, InsufficientPrivilegesException, InternalException {
+        // dataset access for the user has been checked so the REST session for the
+        // reader account can be used if the IDS setting to allow this is enabled
+        long min = result.getJsonNumber(0).longValueExact();
+        long max = result.getJsonNumber(1).longValueExact();
+        long count = result.getJsonNumber(2).longValueExact();
+        logger.debug("manyDfs min: {} max: {} count: {}", min, max, count);
+        if (count != 0) {
+            if (count <= maxEntities) {
+                String query = "SELECT df.id, df.name, df.location, df.createId, df.modId FROM Datafile df WHERE df.dataset.id = "
+                        + dsid + " AND df.location IS NOT NULL AND df.id BETWEEN " + min + " AND " + max;
+                result = Json.createReader(new ByteArrayInputStream(restSessionToUse.search(query).getBytes())).readArray();
+                for (JsonValue tupV : result) {
+                    JsonArray tup = (JsonArray) tupV;
+                    long dfid = tup.getJsonNumber(0).longValueExact();
+                    String location = LocationHelper.getLocation(dfid, tup.getString(2, null));
+                    dfInfos.put(dfid,
+                            new DatafileInfo(dfid, tup.getString(1), location, tup.getString(3), tup.getString(4), dsid));
+                }
+            } else {
+                long half = (min + max) / 2;
+                String query = "SELECT min(df.id), max(df.id), count(df.id) FROM Datafile df WHERE df.dataset.id = "
+                        + dsid + " AND df.location IS NOT NULL AND df.id BETWEEN " + min + " AND " + half;
+                result = Json.createReader(new ByteArrayInputStream(restSessionToUse.search(query).getBytes())).readArray()
+                        .getJsonArray(0);
+                manyDfs(dfInfos, dsid, restSessionToUse, result);
+                query = "SELECT min(df.id), max(df.id), count(df.id) FROM Datafile df WHERE df.dataset.id = " + dsid
+                        + " AND df.location IS NOT NULL AND df.id BETWEEN " + (half + 1) + " AND " + max;
+                result = Json.createReader(new ByteArrayInputStream(restSessionToUse.search(query).getBytes())).readArray()
+                        .getJsonArray(0);
+                manyDfs(dfInfos, dsid, restSessionToUse, result);
+            }
+        }
+    }
+
+    private void manyDss(Map<Long, DataInfoBase> dsInfos, HashSet<Long> emptyDatasets, Map<Long, DataInfoBase> dfInfos, Long invid, boolean dfWanted, Session userRestSession, Session restSessionToUseForDfs, JsonArray result)
             throws IcatException, InsufficientPrivilegesException, InternalException {
         long min = result.getJsonNumber(0).longValueExact();
         long max = result.getJsonNumber(1).longValueExact();
@@ -231,7 +363,7 @@ private void manyDss(Long invid, JsonArray result)
                 for (JsonValue tupV : result) {
                     JsonArray tup = (JsonArray) tupV;
                     long dsid = tup.getJsonNumber(0).longValueExact();
-                    dsInfos.put(dsid, new DsInfoImpl(dsid, tup.getString(1), tup.getString(2, null), invid, invName,
+                    dsInfos.put(dsid, new DatasetInfo(dsid, tup.getString(1), tup.getString(2, null), invid, invName,
                             visitId, facilityId, facilityName));
 
                     query = "SELECT min(df.id), max(df.id), count(df.id) FROM Datafile df WHERE df.dataset.id = "
@@ -241,7 +373,7 @@ private void manyDss(Long invid, JsonArray result)
                     if (result.getJsonNumber(2).longValueExact() == 0) {
                         emptyDatasets.add(dsid);
                     } else if (dfWanted) {
-                        manyDfs(dsid, result);
+                        manyDfs(dfInfos, dsid, restSessionToUseForDfs, result);
                     }
 
                 }
@@ -250,78 +382,58 @@ private void manyDss(Long invid, JsonArray result)
                 String query = "SELECT min(ds.id), max(ds.id), count(ds.id) FROM Dataset ds WHERE ds.investigation.id = "
                         + invid + " AND ds.id BETWEEN " + min + " AND " + half;
                 result = Json.createReader(new ByteArrayInputStream(userRestSession.search(query).getBytes())).readArray();
-                manyDss(invid, result);
+                manyDss(dsInfos, emptyDatasets, dfInfos, invid, dfWanted, userRestSession, restSessionToUseForDfs, result);
                 query = "SELECT min(ds.id), max(ds.id), count(ds.id) FROM Dataset ds WHERE ds.investigation.id = "
                         + invid + " AND ds.id BETWEEN " + half + 1 + " AND " + max;
                 result = Json.createReader(new ByteArrayInputStream(userRestSession.search(query).getBytes())).readArray()
                         .getJsonArray(0);
-                manyDss(invid, result);
+                manyDss(dsInfos, emptyDatasets, dfInfos, invid, dfWanted, userRestSession, restSessionToUseForDfs, result);
             }
         }
 
     }
 
-    private void manyDfs(long dsid, JsonArray result)
-            throws IcatException, InsufficientPrivilegesException, InternalException {
-        // dataset access for the user has been checked so the REST session for the
-        // reader account can be used if the IDS setting to allow this is enabled
-        long min = result.getJsonNumber(0).longValueExact();
-        long max = result.getJsonNumber(1).longValueExact();
-        long count = result.getJsonNumber(2).longValueExact();
-        logger.debug("manyDfs min: {} max: {} count: {}", min, max, count);
-        if (count != 0) {
-            if (count <= maxEntities) {
-                String query = "SELECT df.id, df.name, df.location, df.createId, df.modId FROM Datafile df WHERE df.dataset.id = "
-                        + dsid + " AND df.location IS NOT NULL AND df.id BETWEEN " + min + " AND " + max;
-                result = Json.createReader(new ByteArrayInputStream(restSessionToUse.search(query).getBytes())).readArray();
-                for (JsonValue tupV : result) {
-                    JsonArray tup = (JsonArray) tupV;
-                    long dfid = tup.getJsonNumber(0).longValueExact();
-                    String location = IdsBean.getLocation(dfid, tup.getString(2, null));
-                    dfInfos.add(
-                            new DfInfoImpl(dfid, tup.getString(1), location, tup.getString(3), tup.getString(4), dsid));
-                }
-            } else {
-                long half = (min + max) / 2;
-                String query = "SELECT min(df.id), max(df.id), count(df.id) FROM Datafile df WHERE df.dataset.id = "
-                        + dsid + " AND df.location IS NOT NULL AND df.id BETWEEN " + min + " AND " + half;
-                result = Json.createReader(new ByteArrayInputStream(restSessionToUse.search(query).getBytes())).readArray()
-                        .getJsonArray(0);
-                manyDfs(dsid, result);
-                query = "SELECT min(df.id), max(df.id), count(df.id) FROM Datafile df WHERE df.dataset.id = " + dsid
-                        + " AND df.location IS NOT NULL AND df.id BETWEEN " + (half + 1) + " AND " + max;
-                result = Json.createReader(new ByteArrayInputStream(restSessionToUse.search(query).getBytes())).readArray()
-                        .getJsonArray(0);
-                manyDfs(dsid, result);
-            }
+    private void createRequestTypeToReturnsMapping() throws InternalException {
+
+        this.requestTypeToReturnsMapping = new HashMap<RequestType, Returns>();
+        StorageUnit storageUnit = this.propertyHandler.getStorageUnit();
+
+        this.requestTypeToReturnsMapping.put(RequestType.DELETE, Returns.DATASETS_AND_DATAFILES);
+        this.requestTypeToReturnsMapping.put(RequestType.GETDATAFILEIDS, Returns.DATAFILES);
+        this.requestTypeToReturnsMapping.put(RequestType.GETSIZE, Returns.DATASETS_AND_DATAFILES);
+        this.requestTypeToReturnsMapping.put(RequestType.PREPAREDATA, Returns.DATASETS_AND_DATAFILES);
+        this.requestTypeToReturnsMapping.put(RequestType.RESET, Returns.DATASETS_AND_DATAFILES);
+        this.requestTypeToReturnsMapping.put(RequestType.WRITE, Returns.DATASETS_AND_DATAFILES);
+        this.requestTypeToReturnsMapping.put(RequestType.GETDATA, Returns.DATASETS_AND_DATAFILES);
+
+        if(storageUnit == null ) {
+            this.requestTypeToReturnsMapping.put(RequestType.GETSTATUS, Returns.DATASETS);
+        }
+        else if (storageUnit == StorageUnit.DATAFILE) {
+            this.requestTypeToReturnsMapping.put(RequestType.GETSTATUS, Returns.DATAFILES);
+            this.requestTypeToReturnsMapping.put(RequestType.RESTORE, Returns.DATAFILES);
+            this.requestTypeToReturnsMapping.put(RequestType.ARCHIVE, Returns.DATAFILES);
+        }
+        else if(storageUnit == StorageUnit.DATASET) {
+            this.requestTypeToReturnsMapping.put(RequestType.GETSTATUS, Returns.DATASETS);
+            this.requestTypeToReturnsMapping.put(RequestType.RESTORE, Returns.DATASETS);
+            this.requestTypeToReturnsMapping.put(RequestType.ARCHIVE, Returns.DATASETS);
         }
-    }
 
-    public Map<Long, DsInfo> getDsInfo() {
-        return dsInfos;
-    }
 
-    public Set<DfInfoImpl> getDfInfo() {
-        return dfInfos;
+        else throw new InternalException("StorageUnit " + storageUnit + " unknown. Maybe you forgot to handle a new StorageUnit here?");
     }
 
-    public boolean mustZip() {
-        return dfids.size() > 1L || !dsids.isEmpty() || !invids.isEmpty()
-                || (dfids.isEmpty() && dsids.isEmpty() && invids.isEmpty());
-    }
+    private Returns getReturns(RequestType requestType) throws NotImplementedException {
 
-    public boolean isSingleDataset() {
-        return dfids.isEmpty() && dsids.size() == 1 && invids.isEmpty();
-    }
+        if(this.requestTypeToReturnsMapping.containsKey(requestType))
+            return this.requestTypeToReturnsMapping.get(requestType);
 
-    public Set<Long> getEmptyDatasets() {
-        return emptyDatasets;
-    }
+        
+        // is this needed here?
+        //if(this.propertyHandler.getStorageUnit() == null) throw new NotImplementedException("This operation is unavailable for single level storage");
 
-    public OptionalLong getFileLength() {
-        if (!dfWanted || mustZip()) {
-            return OptionalLong.empty();
-        }
-        return OptionalLong.of(length);
+        throw new NotImplementedException("There is to mapping for RequestType." + requestType + " and StorageUnit." + this.propertyHandler.getStorageUnit() + " defined. Did you forgot to register it in createRequestTypeToReturnsMapping()?");
     }
+
 }
diff --git a/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForSingleLevelStorage.java b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForSingleLevelStorage.java
new file mode 100644
index 00000000..b7915daa
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForSingleLevelStorage.java
@@ -0,0 +1,57 @@
+package org.icatproject.ids.services.dataSelectionService;
+
+import java.util.List;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.TreeMap;
+
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.models.DataInfoBase;
+
+public class DataSelectionServiceForSingleLevelStorage extends DataSelectionService {
+
+    protected DataSelectionServiceForSingleLevelStorage(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos,
+            Set<Long> emptyDatasets, List<Long> invids2, List<Long> dsids, List<Long> dfids, long length, Boolean zip, Boolean compress, RequestType requestType) {
+                
+        super(dsInfos, dfInfos, emptyDatasets, invids2, dsids, dfids, length, zip, compress, requestType);
+    }
+
+
+    @Override
+    public SortedMap<Long, DataInfoBase> getPrimaryDataInfos() {
+        return new TreeMap<Long, DataInfoBase>();
+    }
+
+
+    @Override
+    public boolean existsInMainStorage(DataInfoBase dataInfo) throws InternalException {
+        
+        throw new InternalException("This operation is unavailable for single level storage");
+    }
+
+
+    @Override
+    public boolean isPrepared(String preparedId) throws InternalException {
+        return true;
+    }
+
+
+    @Override
+    public void queueDelete() throws NotImplementedException, InternalException {
+        //nothing todo for single level storage
+    }
+    
+
+    @Override
+    public void scheduleTasks(DeferredOp operation) throws NotImplementedException, InternalException {
+
+        throw new NotImplementedException("This operation is unavailable for single level storage");
+    }
+
+
+    
+    
+}
diff --git a/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForStorageUnitDatafile.java b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForStorageUnitDatafile.java
new file mode 100644
index 00000000..f744fa8f
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForStorageUnitDatafile.java
@@ -0,0 +1,54 @@
+package org.icatproject.ids.services.dataSelectionService;
+
+import java.util.List;
+import java.util.Set;
+import java.util.SortedMap;
+
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.services.ServiceProvider;
+
+public class DataSelectionServiceForStorageUnitDatafile extends DataSelectionService {
+
+    protected DataSelectionServiceForStorageUnitDatafile(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos,
+            Set<Long> emptyDatasets, List<Long> invids2, List<Long> dsids, List<Long> dfids, long length, Boolean zip, Boolean compress, RequestType requestType) {
+
+        super(dsInfos, dfInfos, emptyDatasets, invids2, dsids, dfids, length, zip, compress, requestType);
+    }
+
+
+    @Override
+    public SortedMap<Long, DataInfoBase> getPrimaryDataInfos() {
+        return this.dataSelection.getDfInfo();
+    }
+
+    @Override
+    public boolean existsInMainStorage(DataInfoBase dataInfo) throws InternalException {
+        return ServiceProvider.getInstance().getMainStorage().exists(dataInfo.getLocation());
+    }
+
+
+    @Override
+    public boolean isPrepared(String preparedId) throws InternalException {
+        return areDataInfosPrepared(preparedId);
+    }
+
+
+    @Override
+    public void queueDelete() throws NotImplementedException, InternalException {
+        this.scheduleTasks(DeferredOp.DELETE);
+    }
+
+
+    @Override
+    public void scheduleTasks(DeferredOp operation) throws NotImplementedException, InternalException {
+
+        for (DataInfoBase dataInfo : this.getPrimaryDataInfos().values()) {
+            ServiceProvider.getInstance().getFsm().queue(dataInfo, operation);
+        }
+    }
+    
+}
diff --git a/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForStorageUnitDataset.java b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForStorageUnitDataset.java
new file mode 100644
index 00000000..ff1b5c65
--- /dev/null
+++ b/src/main/java/org/icatproject/ids/services/dataSelectionService/DataSelectionServiceForStorageUnitDataset.java
@@ -0,0 +1,60 @@
+package org.icatproject.ids.services.dataSelectionService;
+
+import java.util.List;
+import java.util.Set;
+import java.util.SortedMap;
+
+import org.icatproject.ids.enums.DeferredOp;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.exceptions.NotImplementedException;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.services.ServiceProvider;
+
+public class DataSelectionServiceForStorageUnitDataset extends DataSelectionService {
+
+    protected DataSelectionServiceForStorageUnitDataset(SortedMap<Long, DataInfoBase> dsInfos, SortedMap<Long, DataInfoBase> dfInfos,
+            Set<Long> emptyDatasets, List<Long> invids2, List<Long> dsids, List<Long> dfids, long length, Boolean zip, Boolean compress, RequestType requestType) {
+
+        super(dsInfos, dfInfos, emptyDatasets, invids2, dsids, dfids, length, zip, compress, requestType);
+    }
+
+
+    @Override
+    public SortedMap<Long, DataInfoBase> getPrimaryDataInfos() {
+        return this.dataSelection.getDsInfo();
+    }
+
+    @Override
+    public boolean existsInMainStorage(DataInfoBase dataInfo) throws InternalException {
+
+        var dsInfo = (DatasetInfo) dataInfo;
+        if(dsInfo == null) throw new InternalException("Could not cast DataInfoBase to DataSetInfo. Did you handed over another sub type?");
+        
+        return this.dataSelection.getEmptyDatasets().contains(dataInfo.getId()) || ServiceProvider.getInstance().getMainStorage().exists(dsInfo);
+    }
+
+
+    @Override
+    public boolean isPrepared(String preparedId) throws InternalException {
+        return this.areDataInfosPrepared(preparedId);
+    }
+
+
+    @Override
+    public void queueDelete() throws NotImplementedException, InternalException {
+        this.scheduleTasks(DeferredOp.WRITE);
+    }
+
+
+    @Override
+    public void scheduleTasks(DeferredOp operation) throws NotImplementedException, InternalException {
+
+        for (DataInfoBase dataInfo : this.getPrimaryDataInfos().values()) {
+            ServiceProvider.getInstance().getFsm().queue(dataInfo, operation);
+        }
+    }
+      
+
+}
diff --git a/src/main/java/org/icatproject/ids/thread/DfArchiver.java b/src/main/java/org/icatproject/ids/thread/DfArchiver.java
index cebdbb11..15df979f 100644
--- a/src/main/java/org/icatproject/ids/thread/DfArchiver.java
+++ b/src/main/java/org/icatproject/ids/thread/DfArchiver.java
@@ -7,12 +7,11 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
-import org.icatproject.ids.plugin.DfInfo;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.models.DatafileInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /*
  * Removes datafiles from the fast storage (doesn't write them to archive storage)
@@ -22,11 +21,11 @@ public class DfArchiver implements Runnable {
 
     private MainStorageInterface mainStorageInterface;
     private FiniteStateMachine fsm;
-    private List<DfInfo> dfInfos;
+    private List<DatafileInfo> dfInfos;
     private Path markerDir;
     private Collection<Lock> locks;
 
-    public DfArchiver(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
+    public DfArchiver(List<DatafileInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
         this.dfInfos = dfInfos;
         this.fsm = fsm;
         this.locks = locks;
@@ -37,7 +36,7 @@ public DfArchiver(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteS
     @Override
     public void run() {
         try {
-            for (DfInfo dfInfo : dfInfos) {
+            for (DatafileInfo dfInfo : dfInfos) {
                 try {
                     if (Files.exists(markerDir.resolve(Long.toString(dfInfo.getDfId())))) {
                         logger.error("Archive of " + dfInfo
diff --git a/src/main/java/org/icatproject/ids/thread/DfDeleter.java b/src/main/java/org/icatproject/ids/thread/DfDeleter.java
index 71b8a569..e0b4dab6 100644
--- a/src/main/java/org/icatproject/ids/thread/DfDeleter.java
+++ b/src/main/java/org/icatproject/ids/thread/DfDeleter.java
@@ -5,12 +5,11 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.models.DatafileInfo;
 import org.icatproject.ids.plugin.ArchiveStorageInterface;
-import org.icatproject.ids.plugin.DfInfo;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /**
  * Delete datafiles from archive
@@ -21,10 +20,10 @@ public class DfDeleter implements Runnable {
 
     private FiniteStateMachine fsm;
     private ArchiveStorageInterface archiveStorageInterface;
-    private List<DfInfo> dfInfos;
+    private List<DatafileInfo> dfInfos;
     private Collection<Lock> locks;
 
-    public DfDeleter(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
+    public DfDeleter(List<DatafileInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
         this.dfInfos = dfInfos;
         this.fsm = fsm;
         this.locks = locks;
@@ -34,7 +33,7 @@ public DfDeleter(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteSt
     @Override
     public void run() {
         try {
-            for (DfInfo dfInfo : dfInfos) {
+            for (DatafileInfo dfInfo : dfInfos) {
                 try {
                     String dfLocation = dfInfo.getDfLocation();
                     archiveStorageInterface.delete(dfLocation);
diff --git a/src/main/java/org/icatproject/ids/thread/DfRestorer.java b/src/main/java/org/icatproject/ids/thread/DfRestorer.java
index 819922b5..a97327b5 100644
--- a/src/main/java/org/icatproject/ids/thread/DfRestorer.java
+++ b/src/main/java/org/icatproject/ids/thread/DfRestorer.java
@@ -1,5 +1,6 @@
 package org.icatproject.ids.thread;
 
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
@@ -7,13 +8,13 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.models.DatafileInfo;
 import org.icatproject.ids.plugin.ArchiveStorageInterface;
 import org.icatproject.ids.plugin.DfInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /*
  * Restores datafiles from the slow to the fast storage.
@@ -25,11 +26,11 @@ public class DfRestorer implements Runnable {
     private MainStorageInterface mainStorageInterface;
     private ArchiveStorageInterface archiveStorageInterface;
     private FiniteStateMachine fsm;
-    private List<DfInfo> dfInfos;
+    private List<DatafileInfo> dataFileInfos;
     private Collection<Lock> locks;
 
-    public DfRestorer(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
-        this.dfInfos = dfInfos;
+    public DfRestorer(List<DatafileInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
+        this.dataFileInfos = dfInfos;
         this.fsm = fsm;
         this.locks = locks;
 
@@ -51,17 +52,24 @@ public void run() {
              * generally remove anything from the list of files to restore as
              * pointless restores are normally filtered out earlier.
              */
-            Iterator<DfInfo> iter = dfInfos.iterator();
+            Iterator<DatafileInfo> iter = dataFileInfos.iterator();
             while (iter.hasNext()) {
-                DfInfo dfInfo = iter.next();
+                DatafileInfo dfInfo = iter.next();
                 if (mainStorageInterface.exists(dfInfo.getDfLocation())) {
                     iter.remove();
                     fsm.removeFromChanging(dfInfo);
                 }
             }
 
+            //TODO: This is additional conversion caused by the redesign :-(
+            List<DfInfo> dfInfos = new ArrayList<>();
+            for(DfInfo dfInfo : this.dataFileInfos) {
+                dfInfos.add(dfInfo);
+            }
+
+
             Set<DfInfo> failures = archiveStorageInterface.restore(mainStorageInterface, dfInfos);
-            for (DfInfo dfInfo : dfInfos) {
+            for (DatafileInfo dfInfo : dataFileInfos) {
                 if (failures.contains(dfInfo)) {
                     fsm.recordFailure(dfInfo.getDfId());
                     logger.error("Restore of " + dfInfo + " failed");
@@ -72,7 +80,7 @@ public void run() {
                 fsm.removeFromChanging(dfInfo);
             }
         } catch (Exception e) {
-            for (DfInfo dfInfo : dfInfos) {
+            for (DatafileInfo dfInfo : dataFileInfos) {
                 logger.error("Restore of " + dfInfo + " failed " + e.getClass() + " " + e.getMessage());
                 fsm.removeFromChanging(dfInfo);
             }
diff --git a/src/main/java/org/icatproject/ids/thread/DfWriter.java b/src/main/java/org/icatproject/ids/thread/DfWriter.java
index d22baf49..09881acc 100644
--- a/src/main/java/org/icatproject/ids/thread/DfWriter.java
+++ b/src/main/java/org/icatproject/ids/thread/DfWriter.java
@@ -8,13 +8,12 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.models.DatafileInfo;
 import org.icatproject.ids.plugin.ArchiveStorageInterface;
-import org.icatproject.ids.plugin.DfInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /**
  * Copies datafiles from main to archive
@@ -27,11 +26,11 @@ public class DfWriter implements Runnable {
     private MainStorageInterface mainStorageInterface;
     private ArchiveStorageInterface archiveStorageInterface;
     private Path markerDir;
-    private List<DfInfo> dfInfos;
+    private List<DatafileInfo> dataFileInfos;
     private Collection<Lock> locks;
 
-    public DfWriter(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
-        this.dfInfos = dfInfos;
+    public DfWriter(List<DatafileInfo> dfInfos, PropertyHandler propertyHandler, FiniteStateMachine fsm, Collection<Lock> locks) {
+        this.dataFileInfos = dfInfos;
         this.fsm = fsm;
         this.locks = locks;
         mainStorageInterface = propertyHandler.getMainStorage();
@@ -42,18 +41,18 @@ public DfWriter(List<DfInfo> dfInfos, PropertyHandler propertyHandler, FiniteSta
     @Override
     public void run() {
         try {
-            for (DfInfo dfInfo : dfInfos) {
-                String dfLocation = dfInfo.getDfLocation();
-                try (InputStream is = mainStorageInterface.get(dfLocation, dfInfo.getCreateId(), dfInfo.getModId())) {
+            for (DatafileInfo dataFileInfo : dataFileInfos) {
+                String dfLocation = dataFileInfo.getDfLocation();
+                try (InputStream is = mainStorageInterface.get(dfLocation, dataFileInfo.getCreateId(), dataFileInfo.getModId())) {
                     archiveStorageInterface.put(is, dfLocation);
-                    Path marker = markerDir.resolve(Long.toString(dfInfo.getDfId()));
+                    Path marker = markerDir.resolve(Long.toString(dataFileInfo.getDfId()));
                     Files.deleteIfExists(marker);
                     logger.debug("Removed marker " + marker);
-                    logger.debug("Write of " + dfInfo + " completed");
+                    logger.debug("Write of " + dataFileInfo + " completed");
                 } catch (Exception e) {
-                    logger.error("Write of " + dfInfo + " failed due to " + e.getClass() + " " + e.getMessage());
+                    logger.error("Write of " + dataFileInfo + " failed due to " + e.getClass() + " " + e.getMessage());
                 } finally {
-                    fsm.removeFromChanging(dfInfo);
+                    fsm.removeFromChanging(dataFileInfo);
                 }
             }
         } finally {
diff --git a/src/main/java/org/icatproject/ids/thread/DsArchiver.java b/src/main/java/org/icatproject/ids/thread/DsArchiver.java
index 3bbed5df..81c2c664 100644
--- a/src/main/java/org/icatproject/ids/thread/DsArchiver.java
+++ b/src/main/java/org/icatproject/ids/thread/DsArchiver.java
@@ -5,26 +5,25 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
-import org.icatproject.ids.plugin.DsInfo;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.models.DatasetInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /*
  * Removes datasets from the fast storage (doesn't write them to slow storage)
  */
 public class DsArchiver implements Runnable {
     private final static Logger logger = LoggerFactory.getLogger(DsArchiver.class);
-    private DsInfo dsInfo;
+    private DatasetInfo dsInfo;
 
     private MainStorageInterface mainStorageInterface;
     private FiniteStateMachine fsm;
     private Path markerDir;
     private Lock lock;
 
-    public DsArchiver(DsInfo dsInfo, PropertyHandler propertyHandler, FiniteStateMachine fsm, Lock lock) {
+    public DsArchiver(DatasetInfo dsInfo, PropertyHandler propertyHandler, FiniteStateMachine fsm, Lock lock) {
         this.dsInfo = dsInfo;
         this.fsm = fsm;
         mainStorageInterface = propertyHandler.getMainStorage();
diff --git a/src/main/java/org/icatproject/ids/thread/DsRestorer.java b/src/main/java/org/icatproject/ids/thread/DsRestorer.java
index 8432670d..20c7b49a 100644
--- a/src/main/java/org/icatproject/ids/thread/DsRestorer.java
+++ b/src/main/java/org/icatproject/ids/thread/DsRestorer.java
@@ -16,15 +16,15 @@
 
 import org.icatproject.Datafile;
 import org.icatproject.Dataset;
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.IcatReader;
-import org.icatproject.ids.IdsBean;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.helpers.LocationHelper;
+import org.icatproject.ids.models.DatasetInfo;
 import org.icatproject.ids.plugin.ArchiveStorageInterface;
-import org.icatproject.ids.plugin.DsInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
 import org.icatproject.ids.plugin.ZipMapperInterface;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /*
  * Restores datafiles from the slow to the fast storage.
@@ -33,7 +33,7 @@ public class DsRestorer implements Runnable {
 
     private final static Logger logger = LoggerFactory.getLogger(DsRestorer.class);
 
-    private DsInfo dsInfo;
+    private DatasetInfo dsInfo;
 
     private MainStorageInterface mainStorageInterface;
     private ArchiveStorageInterface archiveStorageInterface;
@@ -46,7 +46,7 @@ public class DsRestorer implements Runnable {
     private ZipMapperInterface zipMapper;
     private Lock lock;
 
-    public DsRestorer(DsInfo dsInfo, PropertyHandler propertyHandler, FiniteStateMachine fsm, IcatReader reader, Lock lock) {
+    public DsRestorer(DatasetInfo dsInfo, PropertyHandler propertyHandler, FiniteStateMachine fsm, IcatReader reader, Lock lock) {
         this.dsInfo = dsInfo;
         this.fsm = fsm;
         zipMapper = propertyHandler.getZipMapper();
@@ -78,7 +78,7 @@ public void run() {
                 if (datafile.getLocation() == null) {
                     continue;
                 }
-                nameToLocalMap.put(datafile.getName(), IdsBean.getLocation(datafile.getId(), datafile.getLocation()));
+                nameToLocalMap.put(datafile.getName(), LocationHelper.getLocation(datafile.getId(), datafile.getLocation()));
                 size += datafile.getFileSize();
                 n++;
             }
diff --git a/src/main/java/org/icatproject/ids/thread/DsWriter.java b/src/main/java/org/icatproject/ids/thread/DsWriter.java
index d196181b..e5c1843b 100644
--- a/src/main/java/org/icatproject/ids/thread/DsWriter.java
+++ b/src/main/java/org/icatproject/ids/thread/DsWriter.java
@@ -14,16 +14,16 @@
 
 import org.icatproject.Datafile;
 import org.icatproject.Dataset;
-import org.icatproject.ids.DfInfoImpl;
-import org.icatproject.ids.FiniteStateMachine;
-import org.icatproject.ids.IcatReader;
-import org.icatproject.ids.IdsBean;
-import org.icatproject.ids.LockManager.Lock;
-import org.icatproject.ids.PropertyHandler;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.helpers.LocationHelper;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DatasetInfo;
 import org.icatproject.ids.plugin.ArchiveStorageInterface;
-import org.icatproject.ids.plugin.DsInfo;
 import org.icatproject.ids.plugin.MainStorageInterface;
 import org.icatproject.ids.plugin.ZipMapperInterface;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.LockManager.Lock;
 
 /**
  * Copies dataset from main to archive
@@ -32,7 +32,7 @@ public class DsWriter implements Runnable {
 
     private final static Logger logger = LoggerFactory.getLogger(DsWriter.class);
     private static final int BUFSIZ = 1024;
-    private DsInfo dsInfo;
+    private DatasetInfo dsInfo;
 
     private FiniteStateMachine fsm;
     private MainStorageInterface mainStorageInterface;
@@ -43,7 +43,7 @@ public class DsWriter implements Runnable {
     private ZipMapperInterface zipMapper;
     private Lock lock;
 
-    public DsWriter(DsInfo dsInfo, PropertyHandler propertyHandler, FiniteStateMachine fsm, IcatReader reader, Lock lock) {
+    public DsWriter(DatasetInfo dsInfo, PropertyHandler propertyHandler, FiniteStateMachine fsm, IcatReader reader, Lock lock) {
         this.dsInfo = dsInfo;
         this.fsm = fsm;
         this.zipMapper = propertyHandler.getZipMapper();
@@ -73,11 +73,11 @@ public void run() {
                     if (datafile.getLocation() == null) {
                         continue;
                     }
-                    String location = IdsBean.getLocation(datafile.getId(), datafile.getLocation());
+                    String location = LocationHelper.getLocation(datafile.getId(), datafile.getLocation());
                     InputStream is = null;
                     try {
                         zos.putNextEntry(new ZipEntry(
-                                zipMapper.getFullEntryName(dsInfo, new DfInfoImpl(datafile.getId(), datafile.getName(),
+                                zipMapper.getFullEntryName(dsInfo, new DatafileInfo(datafile.getId(), datafile.getName(),
                                         location, datafile.getCreateId(), datafile.getModId(), 0L))));
                         is = mainStorageInterface.get(location, datafile.getCreateId(), datafile.getModId());
                         int bytesRead = 0;
diff --git a/src/test/java/org/icatproject/ids/DataSelectionDevTest.java b/src/test/java/org/icatproject/ids/DataSelectionDevTest.java
index 23fa573f..f0ba796e 100644
--- a/src/test/java/org/icatproject/ids/DataSelectionDevTest.java
+++ b/src/test/java/org/icatproject/ids/DataSelectionDevTest.java
@@ -22,6 +22,12 @@
 import org.icatproject.ICAT;
 import org.icatproject.IcatException_Exception;
 import org.icatproject.icat.client.IcatException;
+import org.icatproject.ids.enums.RequestType;
+import org.icatproject.ids.services.ICATGetter;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionService;
+import org.icatproject.ids.services.dataSelectionService.DataSelectionServiceFactory;
 
 /**
  * This test was created to fix issue #115 and was run against the Diamond
@@ -103,12 +109,12 @@ private void setupPropertyHandler()
     @Test
     public void testCreateDataSelection() throws Exception {
         long startMs = System.currentTimeMillis();
-        DataSelection dataSelection = new DataSelection(mockedPropertyHandler, icatReader, userSessionId,
-                investigationIds, datasetIds, datafileIds, DataSelection.Returns.DATASETS_AND_DATAFILES);
+        var dataSelectionFactory = DataSelectionServiceFactory.getInstanceOnlyForTesting(mockedPropertyHandler, icatReader);
+        DataSelectionService dataSelectionService = dataSelectionFactory.getSelectionService(userSessionId,investigationIds, datasetIds, datafileIds, RequestType.GETSIZE);
         System.out.println("Creating DataSelection took " + (System.currentTimeMillis() - startMs) + " ms");
-        System.out.println("DsInfo size: " + dataSelection.getDsInfo().size());
-        System.out.println("DfInfo size: " + dataSelection.getDfInfo().size());
+        System.out.println("DsInfo size: " + dataSelectionService.getDsInfo().size());
+        System.out.println("DfInfo size: " + dataSelectionService.getDfInfo().size());
         // there must be at least one Datafile in the DataSelection
-        assertTrue("message", dataSelection.getDfInfo().size() > 0);
+        assertTrue("message", dataSelectionService.getDfInfo().size() > 0);
     }
 }
diff --git a/src/test/java/org/icatproject/ids/DigestTest.java b/src/test/java/org/icatproject/ids/DigestTest.java
index d372c35e..735e6195 100644
--- a/src/test/java/org/icatproject/ids/DigestTest.java
+++ b/src/test/java/org/icatproject/ids/DigestTest.java
@@ -6,6 +6,7 @@
 import org.junit.Test;
 
 import org.icatproject.ids.exceptions.InsufficientPrivilegesException;
+import org.icatproject.ids.helpers.LocationHelper;
 import org.icatproject.utils.IcatSecurity;
 
 public class DigestTest {
@@ -17,17 +18,17 @@ public class DigestTest {
     public void testCheck() throws Exception {
         String a = location + " " + IcatSecurity.digest(1234567L, location, key);
 
-        assertEquals(location, IdsBean.getLocationFromDigest(1234567L, a, key));
+        assertEquals(location, LocationHelper.getLocationFromDigest(1234567L, a, key));
 
         try {
-            IdsBean.getLocationFromDigest(1234568L, a, key);
+            LocationHelper.getLocationFromDigest(1234568L, a, key);
             fail();
         } catch (InsufficientPrivilegesException e) {
             assertTrue(e.getMessage().contains("does not contain a valid hash"));
         }
 
         try {
-            IdsBean.getLocationFromDigest(1234568L, location, key);
+            LocationHelper.getLocationFromDigest(1234568L, location, key);
             fail();
         } catch (InsufficientPrivilegesException e) {
             assertTrue(e.getMessage().contains("does not contain hash"));
diff --git a/src/test/java/org/icatproject/ids/PreparePackingTest.java b/src/test/java/org/icatproject/ids/PreparePackingTest.java
index 3d1a2293..6b2a857e 100644
--- a/src/test/java/org/icatproject/ids/PreparePackingTest.java
+++ b/src/test/java/org/icatproject/ids/PreparePackingTest.java
@@ -16,9 +16,12 @@
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
-import org.junit.Test;
 
-import org.icatproject.ids.plugin.DsInfo;
+import org.icatproject.ids.models.DatafileInfo;
+import org.icatproject.ids.models.DataInfoBase;
+import org.icatproject.ids.models.DatasetInfo;
+import org.icatproject.ids.models.Prepared;
+import org.junit.Test;
 
 public class PreparePackingTest {
 
@@ -26,68 +29,73 @@ public class PreparePackingTest {
     public void packAndUnpack() throws Exception {
         boolean zip = true;
         boolean compress = false;
-        Map<Long, DsInfo> dsInfos = new HashMap<>();
-        Set<DfInfoImpl> dfInfos = new HashSet<>();
+        Map<Long, DataInfoBase> dsInfos = new HashMap<>();
+        Map<Long, DataInfoBase> dfInfos = new HashMap<>();
         Set<Long> emptyDatasets = new HashSet<>();
 
         long dsid1 = 17L;
         long dsid2 = 18L;
         long invId = 15L;
         long facilityId = 45L;
-        dfInfos.add(new DfInfoImpl(5L, "dfName", "dfLocation", "createId", "modId", dsid1));
+        dfInfos.put(5L, new DatafileInfo(5L, "dfName", "dfLocation", "createId", "modId", dsid1));
 
-        dfInfos.add(new DfInfoImpl(51L, "dfName2", null, "createId", "modId", dsid1));
+        dfInfos.put(51L, new DatafileInfo(51L, "dfName2", null, "createId", "modId", dsid1));
 
-        dsInfos.put(dsid1, new DsInfoImpl(dsid1, "dsName", "dsLocation", invId, "invName",
+        dsInfos.put(dsid1, new DatasetInfo(dsid1, "dsName", "dsLocation", invId, "invName",
                 "visitId", facilityId, "facilityName"));
 
-        dsInfos.put(dsid2, new DsInfoImpl(dsid2, "dsName2", null, invId, "invName", "visitId",
+        dsInfos.put(dsid2, new DatasetInfo(dsid2, "dsName2", null, invId, "invName", "visitId",
                 facilityId, "facilityName"));
 
         emptyDatasets.add(dsid2);
 
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         try (OutputStream stream = new BufferedOutputStream(baos)) {
-            IdsBean.pack(stream, zip, compress, dsInfos, dfInfos, emptyDatasets);
+            Prepared.pack(stream, zip, compress, dsInfos, dfInfos, emptyDatasets, 51);
         }
         System.out.println(baos.toString());
         InputStream stream = new ByteArrayInputStream(baos.toByteArray());
-        Prepared prepared = IdsBean.unpack(stream);
+        Prepared prepared = Prepared.unpack(stream);
         assertTrue(prepared.zip);
         assertFalse(prepared.compress);
-        for (DfInfoImpl dfInfo : prepared.dfInfos) {
-            if (dfInfo.getDfId() == 5L) {
-                assertEquals("dfName", dfInfo.getDfName());
-                assertEquals("dfLocation", dfInfo.getDfLocation());
-            } else if (dfInfo.getDfId() == 51L) {
-                assertEquals("dfName2", dfInfo.getDfName());
-                assertNull(dfInfo.getDfLocation());
+        assertEquals(prepared.fileLength, 51);
+        for (DataInfoBase dataInfo : prepared.dfInfos.values()) {
+            if (dataInfo.getId() == 5L) {
+                assertEquals("dfName", dataInfo.getName());
+                assertEquals("dfLocation", dataInfo.getLocation());
+            } else if (dataInfo.getId() == 51L) {
+                assertEquals("dfName2", dataInfo.getName());
+                assertNull(dataInfo.getLocation());
             } else {
                 fail();
             }
+            var dfInfo = (DatafileInfo) dataInfo;
             assertEquals("createId", dfInfo.getCreateId());
             assertEquals("modId", dfInfo.getModId());
             assertEquals(dsid1, dfInfo.getDsId());
         }
-        for (Entry<Long, DsInfo> entry : prepared.dsInfos.entrySet()) {
+        for (Entry<Long, DataInfoBase> entry : prepared.dsInfos.entrySet()) {
             Long key = entry.getKey();
-            DsInfo value = entry.getValue();
-            assertEquals((Long) key, (Long) value.getDsId());
-            if (value.getDsId() == dsid1) {
-                assertEquals("dsName", value.getDsName());
-                assertEquals("dsLocation", value.getDsLocation());
-            } else if (value.getDsId() == dsid2) {
-                assertEquals("dsName2", value.getDsName());
-                assertNull(value.getDsLocation());
+            DataInfoBase value = entry.getValue();
+            assertEquals((Long) key, (Long) value.getId());
+            if (value.getId() == dsid1) {
+                assertEquals("dsName", value.getName());
+                assertEquals("dsLocation", value.getLocation());
+            } else if (value.getId() == dsid2) {
+                assertEquals("dsName2", value.getName());
+                assertNull(value.getLocation());
             } else {
                 fail();
             }
-            assertEquals((Long) invId, value.getInvId());
-            assertEquals("invName", value.getInvName());
 
-            assertEquals("visitId", value.getVisitId());
-            assertEquals((Long) facilityId, value.getFacilityId());
-            assertEquals("facilityName", value.getFacilityName());
+            var dsInfo = (DatasetInfo) value;
+
+            assertEquals((Long) invId, dsInfo.getInvId());
+            assertEquals("invName", dsInfo.getInvName());
+
+            assertEquals("visitId", dsInfo.getVisitId());
+            assertEquals((Long) facilityId, dsInfo.getFacilityId());
+            assertEquals("facilityName", dsInfo.getFacilityName());
 
         }
         assertEquals(1, prepared.emptyDatasets.size());
diff --git a/src/test/java/org/icatproject/ids/RangeOutputStreamTest.java b/src/test/java/org/icatproject/ids/RangeOutputStreamTest.java
index 2a71dea5..e6960866 100644
--- a/src/test/java/org/icatproject/ids/RangeOutputStreamTest.java
+++ b/src/test/java/org/icatproject/ids/RangeOutputStreamTest.java
@@ -4,6 +4,8 @@
 import java.io.OutputStream;
 
 import static org.junit.Assert.assertEquals;
+
+import org.icatproject.ids.helpers.RangeOutputStream;
 import org.junit.Test;
 
 public class RangeOutputStreamTest {
diff --git a/src/test/java/org/icatproject/ids/TestICATGetter.java b/src/test/java/org/icatproject/ids/TestICATGetter.java
index 806dfa47..8bfa99c6 100644
--- a/src/test/java/org/icatproject/ids/TestICATGetter.java
+++ b/src/test/java/org/icatproject/ids/TestICATGetter.java
@@ -4,6 +4,7 @@
 import org.junit.Test;
 
 import org.icatproject.ICAT;
+import org.icatproject.ids.services.ICATGetter;
 
 public class TestICATGetter {
 
diff --git a/src/test/java/org/icatproject/ids/TestValueContainer.java b/src/test/java/org/icatproject/ids/TestValueContainer.java
new file mode 100644
index 00000000..bc3daf98
--- /dev/null
+++ b/src/test/java/org/icatproject/ids/TestValueContainer.java
@@ -0,0 +1,111 @@
+package org.icatproject.ids;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.io.BufferedReader;
+import java.io.ByteArrayInputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
+import java.util.stream.Collectors;
+
+import org.icatproject.ids.enums.ValueContainerType;
+import org.icatproject.ids.exceptions.InternalException;
+import org.icatproject.ids.helpers.ValueContainer;
+import org.junit.Test;
+
+
+public class TestValueContainer {
+
+    @Test
+    public void testInvalidValueContainer() throws Exception {
+        
+        var vc = ValueContainer.getInvalid();
+        assertFalse(vc.isVoid());
+        assertTrue(vc.getType() == ValueContainerType.INVALID);
+    }
+
+    @Test
+    public void testVoidValueContainer() throws Exception {
+        
+        var vc = ValueContainer.getVoid();
+        assertTrue(vc.isVoid());
+        assertTrue(vc.getType() == ValueContainerType.VOID);
+        assertFalse(vc.isInvalid());
+    }
+
+    @Test(expected = InternalException.class)
+    public void testIntValueContainer() throws Exception {
+        
+        var vc = new ValueContainer(1);
+        assertFalse(vc.isVoid());
+        assertFalse(vc.isInvalid());
+        assertFalse(vc.isNull());
+
+        assertEquals(vc.getInt(), 1);
+
+        vc.getLong();
+    }
+
+    @Test(expected = InternalException.class)
+    public void testLongValueContainer() throws Exception {
+        
+        var vc = new ValueContainer(1L);
+        assertFalse(vc.isVoid());
+        assertFalse(vc.isInvalid());
+        assertFalse(vc.isNull());
+
+        assertEquals(vc.getLong(), 1L);
+
+        vc.getInt();
+    }
+
+    @Test(expected = InternalException.class)
+    public void testBoolValueContainer() throws Exception {
+        
+        var vc = new ValueContainer(true);
+        assertFalse(vc.isVoid());
+        assertFalse(vc.isInvalid());
+        assertFalse(vc.isNull());
+
+        assertEquals(vc.getBool(), true);
+
+        vc.getString();
+    }
+
+    @Test(expected = InternalException.class)
+    public void testStringValueContainer() throws Exception {
+        
+        var vc = new ValueContainer("test");
+        assertFalse(vc.isVoid());
+        assertFalse(vc.isInvalid());
+        assertFalse(vc.isNull());
+
+        assertEquals(vc.getString(), "test");
+
+        vc.getBool();
+    }
+
+    @Test(expected = InternalException.class)
+    public void testInputStreamValueContainer() throws Exception {
+        
+        String s = "test InputStream";
+        var inputStream = new ByteArrayInputStream(s.getBytes());
+        var vc = new ValueContainer(inputStream);
+        assertFalse(vc.isVoid());
+        assertFalse(vc.isInvalid());
+        assertFalse(vc.isNull());
+
+        assertEquals(vc.getInputStream(), inputStream);
+        
+        var ISReader = new InputStreamReader(vc.getInputStream(), StandardCharsets.UTF_8);
+        var BReader = new BufferedReader(ISReader);
+        String textFromStream = BReader.lines().collect(Collectors.joining());
+        BReader.close();
+        assertEquals(textFromStream, s);
+
+        vc.getString();
+    }
+
+}
\ No newline at end of file
diff --git a/src/test/java/org/icatproject/ids/TidierTest.java b/src/test/java/org/icatproject/ids/TidierTest.java
index 77e3f9d1..8f2762c6 100644
--- a/src/test/java/org/icatproject/ids/TidierTest.java
+++ b/src/test/java/org/icatproject/ids/TidierTest.java
@@ -85,19 +85,19 @@ public void testCleanPreparedDir() throws Exception {
     @Test
     public void testAddStringConstraint() throws Exception {
         StringBuilder sb1 = new StringBuilder();
-        boolean andNeeded = Tidier.addStringConstraint(sb1, "df.location", "/path/to/normal/file", false);
+        Tidier.addStringConstraint(sb1, "df.location", "/path/to/normal/file", false);
         assertEquals(" df.location = '/path/to/normal/file'", sb1.toString());
 
         /* Fix error where a file path contains an apostrophe */
         StringBuilder sb2 = new StringBuilder();
-        andNeeded = Tidier.addStringConstraint(sb2, "df.location", "/path/to/Person's Files/myscript.py", false);
+        Tidier.addStringConstraint(sb2, "df.location", "/path/to/Person's Files/myscript.py", false);
         assertEquals(" df.location = '/path/to/Person''s Files/myscript.py'", sb2.toString());
     }
 
     @Test
     public void testAddNumericConstraint() throws Exception {
         StringBuilder sb3 = new StringBuilder();
-        boolean andNeeded = Tidier.addNumericConstraint(sb3, "df.id", 12345L, false);
+        Tidier.addNumericConstraint(sb3, "df.id", 12345L, false);
         assertEquals(" df.id = 12345", sb3.toString());
     }
 }
diff --git a/src/test/java/org/icatproject/ids/TransmittingTest.java b/src/test/java/org/icatproject/ids/TransmittingTest.java
new file mode 100644
index 00000000..7e2e986c
--- /dev/null
+++ b/src/test/java/org/icatproject/ids/TransmittingTest.java
@@ -0,0 +1,278 @@
+package org.icatproject.ids;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.when;
+
+import java.io.ByteArrayInputStream;
+import java.net.URISyntaxException;
+import java.nio.file.Paths;
+
+import org.icatproject.ICAT;
+import org.icatproject.IcatException_Exception;
+import org.icatproject.icat.client.IcatException;
+import org.icatproject.ids.enums.StorageUnit;
+import org.icatproject.ids.finiteStateMachine.FiniteStateMachine;
+import org.icatproject.ids.plugin.ArchiveStorageInterface;
+import org.icatproject.ids.requestHandlers.ArchiveHandler;
+import org.icatproject.ids.requestHandlers.DeleteHandler;
+import org.icatproject.ids.requestHandlers.GetDataFileIdsHandler;
+import org.icatproject.ids.requestHandlers.GetDataHandler;
+import org.icatproject.ids.requestHandlers.GetIcatUrlHandler;
+import org.icatproject.ids.requestHandlers.GetServiceStatusHandler;
+import org.icatproject.ids.requestHandlers.GetStatusHandler;
+import org.icatproject.ids.requestHandlers.IsPreparedHandler;
+import org.icatproject.ids.requestHandlers.IsReadOnlyHandler;
+import org.icatproject.ids.requestHandlers.IsTwoLevelHandler;
+import org.icatproject.ids.requestHandlers.PrepareDataHandler;
+import org.icatproject.ids.requestHandlers.PutHandler;
+import org.icatproject.ids.requestHandlers.ResetHandler;
+import org.icatproject.ids.requestHandlers.RestoreHandler;
+import org.icatproject.ids.requestHandlers.WriteHandler;
+import org.icatproject.ids.requestHandlers.getSizeHandlers.GetSizeHandler;
+import org.icatproject.ids.requestHandlers.getSizeHandlers.GetSizeHandlerForFastProcessing;
+import org.icatproject.ids.services.IcatReader;
+import org.icatproject.ids.services.LockManager;
+import org.icatproject.ids.services.PropertyHandler;
+import org.icatproject.ids.services.ServiceProvider;
+import org.icatproject.ids.services.Transmitter;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+
+/**
+ * This test was created when the building of the transmission body was made more comon and generic. 
+ * It should ensure the right structure of the containing json.
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class TransmittingTest {
+
+    @Mock
+    private PropertyHandler mockedPropertyHandler;
+    @Mock
+    private Transmitter mockedTransmitter;
+    @Mock
+    private FiniteStateMachine mockedFsm;
+    @Mock
+    private LockManager mockedLockManager;
+    @Mock
+    private IcatReader mockedReader;
+    @Mock ArchiveStorageInterface mockedArchiveStorage;
+    @Mock
+    private ICAT mockedIcat;
+
+    private String ip = "192.168.17.1";
+    private String sessionId = "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa";
+    private String preparedId = sessionId;
+    private String investigationIds = "1, 2, 3";
+    private String datasetIds = "4, 5, 6";
+    private String datafileIds = "7, 8, 9";
+    private String defaultTransmissionBodyForPreparedId = "{\"preparedId\":\"aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa\"}";
+    private String defaultTransmissionBodyForSessionId = "{\"userName\":\"TestUser\",\"investigationIds\":[1,2,3],\"datasetIds\":[4,5,6],\"datafileIds\":[7,8,9]}";
+
+    private void setup()
+            throws URISyntaxException, IcatException_Exception, IcatException {
+
+        when(mockedPropertyHandler.getIcatService()).thenReturn(mockedIcat);
+        when(mockedPropertyHandler.getCacheDir()).thenReturn(Paths.get(""));
+        when(mockedPropertyHandler.getStorageUnit()).thenReturn(StorageUnit.DATASET);
+        when(mockedPropertyHandler.getArchiveStorage()).thenReturn(mockedArchiveStorage);
+        when(mockedPropertyHandler.getReadOnly()).thenReturn(false);
+        when(mockedIcat.getUserName("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa")).thenReturn("TestUser");
+
+        ServiceProvider.createInstance(mockedPropertyHandler, mockedTransmitter, mockedFsm, mockedLockManager, mockedReader);
+    }
+
+    @Test
+    public void testTransmitterBodyForArchiveRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new ArchiveHandler(ip, sessionId, investigationIds, datasetIds, datafileIds);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetSizeRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetSizeHandler(ip, preparedId, null, null, null, null);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForPreparedId, body);
+
+        handler = new GetSizeHandler(ip, null, sessionId, investigationIds, datasetIds, datafileIds);
+        body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetSizeFastRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetSizeHandlerForFastProcessing(ip, sessionId, investigationIds, datasetIds, datafileIds);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+
+    }
+
+    @Test
+    public void testTransmitterBodyForDeleteRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new DeleteHandler(ip, sessionId, investigationIds, datasetIds, datafileIds);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetDataFileIdsRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetDataFileIdsHandler(ip, preparedId, null, null, null, null);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForPreparedId, body);
+
+        handler = new GetDataFileIdsHandler("192.168.17.1", null,  sessionId, investigationIds, datasetIds, datafileIds);
+        body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetDataRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetDataHandler(ip, preparedId, null, null, null, null, false, false, "", "");
+        String body = handler.provideTransmissionBody();
+        assertEquals("{\"preparedId\":\"aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa\",\"transferId\":-1}", body);
+
+        handler = new GetDataHandler(ip, null,  sessionId, investigationIds, datasetIds, datafileIds, false, false, "", "");
+        body = handler.provideTransmissionBody();
+        assertEquals("{\"userName\":\"TestUser\",\"investigationIds\":[1,2,3],\"datasetIds\":[4,5,6],\"datafileIds\":[7,8,9],\"transferId\":-1}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetIcatUrlRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetIcatUrlHandler(ip);
+        String body = handler.provideTransmissionBody();
+        assertEquals("{}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetServiceStatusRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetServiceStatusHandler(ip, sessionId);
+        String body = handler.provideTransmissionBody();
+        assertEquals("{\"userName\":\"TestUser\"}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForGetStatusRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new GetStatusHandler(ip, preparedId, null, null, null, null);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForPreparedId, body);
+
+        handler = new GetStatusHandler(ip, null, sessionId, investigationIds, datasetIds, datafileIds);
+        body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForIsPreparedRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new IsPreparedHandler(ip, preparedId);
+        String body = handler.provideTransmissionBody();
+        assertEquals("{\"preparedId\":\"aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa\"}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForIsReadOnlyRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new IsReadOnlyHandler(ip);
+        String body = handler.provideTransmissionBody();
+        assertEquals("{}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForIsTwoLevelRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new IsTwoLevelHandler(ip);
+        String body = handler.provideTransmissionBody();
+        assertEquals("{}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForPrepareDataRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new PrepareDataHandler(ip, sessionId, investigationIds, datasetIds, datafileIds, false, false);
+        String body = handler.provideTransmissionBody();
+        assertEquals("{\"userName\":\"TestUser\",\"investigationIds\":[1,2,3],\"datasetIds\":[4,5,6],\"datafileIds\":[7,8,9],\"preparedId\":\"\"}", body);
+
+    }
+
+    @Test
+    public void testTransmitterBodyForPutRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new PutHandler(ip, sessionId, new ByteArrayInputStream( "".getBytes() ), "someName", datafileIds , datasetIds, "someDescription", "someDOI", "simeCreateTimeString", "someModTimeString", false, false );
+        String body = handler.provideTransmissionBody();
+        assertEquals("{\"userName\":\"TestUser\",\"datafileId\":-1}", body);
+    }
+
+    @Test
+    public void testTransmitterBodyForResetRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new ResetHandler(ip, preparedId, null, null, null, null);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForPreparedId, body);
+
+        handler = new ResetHandler(ip, null, sessionId, investigationIds, datasetIds, datafileIds);
+        body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForRestoreRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new RestoreHandler(ip, sessionId, investigationIds, datasetIds, datafileIds);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+
+    @Test
+    public void testTransmitterBodyForWriteRequest_shouldBeOk() throws Exception {
+        
+        setup();
+
+        var handler = new WriteHandler(ip, sessionId, investigationIds, datasetIds, datafileIds);
+        String body = handler.provideTransmissionBody();
+        assertEquals(defaultTransmissionBodyForSessionId, body);
+    }
+}
diff --git a/src/test/java/org/icatproject/ids/ValidaterTest.java b/src/test/java/org/icatproject/ids/ValidaterTest.java
index 1be98060..6dda09ef 100644
--- a/src/test/java/org/icatproject/ids/ValidaterTest.java
+++ b/src/test/java/org/icatproject/ids/ValidaterTest.java
@@ -5,6 +5,7 @@
 import org.junit.Test;
 
 import org.icatproject.ids.exceptions.BadRequestException;
+import org.icatproject.ids.requestHandlers.base.DataControllerBase;
 
 public class ValidaterTest {
 
@@ -21,7 +22,7 @@ public void testIsValidId() throws Exception {
 
     private void testValidUUID(boolean b, String id) {
         try {
-            IdsBean.validateUUID("testValidUUID", id);
+            DataControllerBase.validateUUID("testValidUUID", id);
             assertTrue(b);
         } catch (BadRequestException e) {
             System.out.println(e.getMessage());
@@ -31,3 +32,4 @@ private void testValidUUID(boolean b, String id) {
     }
 
 }
+
diff --git a/src/test/java/org/icatproject/ids/integration/BaseTest.java b/src/test/java/org/icatproject/ids/integration/BaseTest.java
index 2d4bca96..4f0a23d4 100644
--- a/src/test/java/org/icatproject/ids/integration/BaseTest.java
+++ b/src/test/java/org/icatproject/ids/integration/BaseTest.java
@@ -47,13 +47,13 @@
 import org.icatproject.InvestigationType;
 import org.icatproject.icat.client.ICAT;
 import org.icatproject.icat.client.Session;
-import org.icatproject.ids.ICATGetter;
 import org.icatproject.ids.integration.util.Setup;
 import org.icatproject.ids.integration.util.client.DataSelection;
 import org.icatproject.ids.integration.util.client.TestingClient;
 import org.icatproject.ids.integration.util.client.TestingClient.Flag;
 import org.icatproject.ids.integration.util.client.TestingClient.ServiceStatus;
 import org.icatproject.ids.integration.util.client.TestingClient.Status;
+import org.icatproject.ids.services.ICATGetter;
 
 public class BaseTest {
 
diff --git a/src/test/java/org/icatproject/ids/integration/twodf/MiscTest.java b/src/test/java/org/icatproject/ids/integration/twodf/MiscTest.java
index 482ad9d7..011de0ad 100644
--- a/src/test/java/org/icatproject/ids/integration/twodf/MiscTest.java
+++ b/src/test/java/org/icatproject/ids/integration/twodf/MiscTest.java
@@ -43,7 +43,10 @@ public void correctBehaviourNoOffsetTest() throws Exception {
         String preparedId = testingClient.prepareData(sessionId, new DataSelection().addDatafile(datafileIds.get(0)),
                 Flag.NONE, 200);
 
-        assertFalse(testingClient.getServiceStatus(sessionId, 200).getOpItems().isEmpty());
+        var status = testingClient.getServiceStatus(sessionId, 200);
+        //System.out.println("### twodf.MiscTest.correctBehaviourNoOffsetTest - status: " + status.toString());
+
+        assertFalse(status.getOpItems().isEmpty());
 
         while (!testingClient.isPrepared(preparedId, 200)) {
             Thread.sleep(1000);
diff --git a/src/test/java/org/icatproject/ids/integration/twodf/QueueTest.java b/src/test/java/org/icatproject/ids/integration/twodf/QueueTest.java
index eec87654..baf7be8d 100644
--- a/src/test/java/org/icatproject/ids/integration/twodf/QueueTest.java
+++ b/src/test/java/org/icatproject/ids/integration/twodf/QueueTest.java
@@ -36,7 +36,7 @@ public void multiOperationTest() throws Exception {
         waitForIds();
         assertTrue(Files.exists(dirOnFastStorage));
 
-        Long dfid = testingClient.put(sessionId, Files.newInputStream(newFileLocation),
+        testingClient.put(sessionId, Files.newInputStream(newFileLocation),
                 "uploaded_file_" + timestamp, dsId, supportedDatafileFormat.getId(),
                 "A rather splendid datafile", 201);
         testingClient.archive(sessionId, selection, 204);
diff --git a/src/test/java/org/icatproject/ids/integration/util/Setup.java b/src/test/java/org/icatproject/ids/integration/util/Setup.java
index 8d74494c..2392805d 100644
--- a/src/test/java/org/icatproject/ids/integration/util/Setup.java
+++ b/src/test/java/org/icatproject/ids/integration/util/Setup.java
@@ -10,8 +10,8 @@
 import java.util.Properties;
 
 import org.icatproject.ICAT;
-import org.icatproject.ids.ICATGetter;
 import org.icatproject.ids.TestUtils;
+import org.icatproject.ids.services.ICATGetter;
 import org.icatproject.utils.CheckedProperties;
 import org.icatproject.utils.ShellCommand;
 
diff --git a/src/test/java/org/icatproject/ids/integration/util/client/TestingClient.java b/src/test/java/org/icatproject/ids/integration/util/client/TestingClient.java
index f6f68e64..7bb22543 100644
--- a/src/test/java/org/icatproject/ids/integration/util/client/TestingClient.java
+++ b/src/test/java/org/icatproject/ids/integration/util/client/TestingClient.java
@@ -7,8 +7,6 @@
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
-import java.nio.file.Path;
-import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.HashMap;
@@ -48,6 +46,8 @@
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.message.BasicNameValuePair;
 import org.apache.http.util.EntityUtils;
+import org.icatproject.ids.enums.RequestIdNames;
+
 import static org.junit.Assert.fail;
 
 public class TestingClient {
@@ -103,6 +103,20 @@ void storeFailure(Long id) {
             failures.add(id);
         }
 
+        @Override
+        public String toString() {
+            String result = "lockCount: " + this.lockCount + ", ";
+            result += "lockedIDs: " + lockedDs.size() + "\n";
+            for(long lockedId : lockedDs) result += "\t" + lockedId + "\n";
+            result += "opItems: " + opItems.size() + "\n";
+            for(String key : opItems.keySet()) result += "\t" + key + ": " + opItems.get(key) + "\n";
+            result += "failures: " + failures.size() + "\n";
+            for(long fail : failures) result += " " + fail;
+            result += "\n";
+
+            return result;
+        }
+
     }
 
     public enum Status {
@@ -128,7 +142,7 @@ public void archive(String sessionId, DataSelection data, Integer sc) throws Not
 
         URI uri = getUri(getUriBuilder("archive"));
         List<NameValuePair> formparams = new ArrayList<>();
-        formparams.add(new BasicNameValuePair("sessionId", sessionId));
+        formparams.add(new BasicNameValuePair(RequestIdNames.sessionId, sessionId));
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             formparams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
         }
@@ -217,7 +231,7 @@ public void delete(String sessionId, DataSelection data, Integer sc)
             NotFoundException, DataNotOnlineException {
 
         URIBuilder uriBuilder = getUriBuilder("delete");
-        uriBuilder.addParameter("sessionId", sessionId);
+        uriBuilder.addParameter(RequestIdNames.sessionId, sessionId);
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             uriBuilder.addParameter(entry.getKey(), entry.getValue());
         }
@@ -268,7 +282,7 @@ public InputStream getData(String sessionId, DataSelection data, Flag flags, lon
             InternalException, DataNotOnlineException {
 
         URIBuilder uriBuilder = getUriBuilder("getData");
-        uriBuilder.setParameter("sessionId", sessionId);
+        uriBuilder.setParameter(RequestIdNames.sessionId, sessionId);
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             uriBuilder.setParameter(entry.getKey(), entry.getValue());
         }
@@ -320,7 +334,7 @@ public InputStream getData(String preparedId, long offset, Integer sc)
             InternalException, DataNotOnlineException {
 
         URIBuilder uriBuilder = getUriBuilder("getData");
-        uriBuilder.setParameter("preparedId", preparedId);
+        uriBuilder.setParameter(RequestIdNames.preparedId, preparedId);
         URI uri = getUri(uriBuilder);
 
         CloseableHttpResponse response = null;
@@ -361,7 +375,7 @@ public ServiceStatus getServiceStatus(String sessionId, Integer sc)
             throws InternalException, InsufficientPrivilegesException, NotImplementedException {
 
         URIBuilder uriBuilder = getUriBuilder("getServiceStatus");
-        uriBuilder.setParameter("sessionId", sessionId);
+        uriBuilder.setParameter(RequestIdNames.sessionId, sessionId);
         URI uri = getUri(uriBuilder);
 
         try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
@@ -406,7 +420,7 @@ public long getSize(String sessionId, DataSelection data, int sc) throws BadRequ
             InsufficientPrivilegesException, InternalException, NotImplementedException {
 
         URIBuilder uriBuilder = getUriBuilder("getSize");
-        uriBuilder.setParameter("sessionId", sessionId);
+        uriBuilder.setParameter(RequestIdNames.sessionId, sessionId);
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             uriBuilder.setParameter(entry.getKey(), entry.getValue());
         }
@@ -429,7 +443,7 @@ public long getSize(String preparedId, int sc) throws BadRequestException, NotFo
             InsufficientPrivilegesException, InternalException, NotImplementedException {
 
         URIBuilder uriBuilder = getUriBuilder("getSize");
-        uriBuilder.setParameter("preparedId", preparedId);
+        uriBuilder.setParameter(RequestIdNames.preparedId, preparedId);
         URI uri = getUri(uriBuilder);
 
         try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
@@ -449,7 +463,7 @@ public Status getStatus(String sessionId, DataSelection data, Integer sc) throws
 
         URIBuilder uriBuilder = getUriBuilder("getStatus");
         if (sessionId != null) {
-            uriBuilder.setParameter("sessionId", sessionId);
+            uriBuilder.setParameter(RequestIdNames.sessionId, sessionId);
         }
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             uriBuilder.setParameter(entry.getKey(), entry.getValue());
@@ -475,7 +489,7 @@ public Status getStatus(String preparedId, Integer sc) throws BadRequestExceptio
             NotFoundException, InsufficientPrivilegesException, InternalException, NotImplementedException {
 
         URIBuilder uriBuilder = getUriBuilder("getStatus");
-        uriBuilder.setParameter("preparedId", preparedId);
+        uriBuilder.setParameter(RequestIdNames.preparedId, preparedId);
         URI uri = getUri(uriBuilder);
 
         try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
@@ -519,7 +533,7 @@ public boolean isPrepared(String preparedId, Integer sc)
             throws BadRequestException, NotFoundException, InternalException, NotImplementedException {
 
         URIBuilder uriBuilder = getUriBuilder("isPrepared");
-        uriBuilder.setParameter("preparedId", preparedId);
+        uriBuilder.setParameter(RequestIdNames.preparedId, preparedId);
         URI uri = getUri(uriBuilder);
 
         try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
@@ -594,7 +608,7 @@ public String prepareData(String sessionId, DataSelection data, Flag flags, Inte
 
         URI uri = getUri(getUriBuilder("prepareData"));
         List<NameValuePair> formparams = new ArrayList<>();
-        formparams.add(new BasicNameValuePair("sessionId", sessionId));
+        formparams.add(new BasicNameValuePair(RequestIdNames.sessionId, sessionId));
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             formparams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
         }
@@ -638,7 +652,7 @@ public Long put(String sessionId, InputStream inputStream, String name, long dat
         CRC32 crc = new CRC32();
         inputStream = new CheckedInputStream(inputStream, crc);
         URIBuilder uriBuilder = getUriBuilder("put");
-        uriBuilder.setParameter("sessionId", sessionId).setParameter("name", name)
+        uriBuilder.setParameter(RequestIdNames.sessionId, sessionId).setParameter("name", name)
                 .setParameter("datafileFormatId", Long.toString(datafileFormatId))
                 .setParameter("datasetId", Long.toString(datasetId));
         if (description != null) {
@@ -690,7 +704,7 @@ public Long putAsPost(String sessionId, InputStream inputStream, String name, lo
         URI uri = getUri(getUriBuilder("put"));
 
         MultipartEntityBuilder reqEntityBuilder = MultipartEntityBuilder.create()
-                .addPart("sessionId", new StringBody(sessionId, ContentType.TEXT_PLAIN))
+                .addPart(RequestIdNames.sessionId, new StringBody(sessionId, ContentType.TEXT_PLAIN))
                 .addPart("datafileFormatId", new StringBody(Long.toString(datafileFormatId), ContentType.TEXT_PLAIN))
                 .addPart("name", new StringBody(name, ContentType.TEXT_PLAIN))
                 .addPart("datasetId", new StringBody(Long.toString(datasetId), ContentType.TEXT_PLAIN));
@@ -747,7 +761,7 @@ public void restore(String sessionId, DataSelection data, Integer sc) throws Not
 
         URI uri = getUri(getUriBuilder("restore"));
         List<NameValuePair> formparams = new ArrayList<>();
-        formparams.add(new BasicNameValuePair("sessionId", sessionId));
+        formparams.add(new BasicNameValuePair(RequestIdNames.sessionId, sessionId));
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             formparams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
         }
@@ -769,7 +783,7 @@ public List<Long> getDatafileIds(String preparedId, Integer sc)
             throws InternalException, BadRequestException, NotFoundException {
 
         URIBuilder uriBuilder = getUriBuilder("getDatafileIds");
-        uriBuilder.setParameter("preparedId", preparedId);
+        uriBuilder.setParameter(RequestIdNames.preparedId, preparedId);
         URI uri = getUri(uriBuilder);
 
         try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
@@ -804,7 +818,7 @@ public List<Long> getDatafileIds(String preparedId, Integer sc)
     public List<Long> getDatafileIds(String sessionId, DataSelection data, Integer sc)
             throws InternalException, BadRequestException, ParseException, NotFoundException {
         URIBuilder uriBuilder = getUriBuilder("getDatafileIds");
-        uriBuilder.setParameter("sessionId", sessionId);
+        uriBuilder.setParameter(RequestIdNames.sessionId, sessionId);
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             uriBuilder.setParameter(entry.getKey(), entry.getValue());
         }
@@ -843,7 +857,7 @@ public void reset(String preparedId, Integer sc) throws InternalException, BadRe
             InsufficientPrivilegesException, NotImplementedException, NotFoundException {
         URI uri = getUri(getUriBuilder("reset"));
         List<NameValuePair> formparams = new ArrayList<>();
-        formparams.add(new BasicNameValuePair("preparedId", preparedId));
+        formparams.add(new BasicNameValuePair(RequestIdNames.preparedId, preparedId));
 
         try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
             HttpEntity entity = new UrlEncodedFormEntity(formparams);
@@ -863,7 +877,7 @@ public void reset(String sessionId, DataSelection data, int sc) throws InternalE
             ParseException, InsufficientPrivilegesException, NotImplementedException, NotFoundException {
         URI uri = getUri(getUriBuilder("reset"));
         List<NameValuePair> formparams = new ArrayList<>();
-        formparams.add(new BasicNameValuePair("sessionId", sessionId));
+        formparams.add(new BasicNameValuePair(RequestIdNames.sessionId, sessionId));
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             formparams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
         }
@@ -887,7 +901,7 @@ public void write(String sessionId, DataSelection data, Integer sc) throws NotIm
 
         URI uri = getUri(getUriBuilder("write"));
         List<NameValuePair> formparams = new ArrayList<>();
-        formparams.add(new BasicNameValuePair("sessionId", sessionId));
+        formparams.add(new BasicNameValuePair(RequestIdNames.sessionId, sessionId));
         for (Entry<String, String> entry : data.getParameters().entrySet()) {
             formparams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
         }