Introduce ListableStepLocator

fmbenhassine · fmbenhassine · commit 0b1d9203fe08 · 2025-10-08T10:35:57.000+02:00
Resolves #5015
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/configuration/support/DefaultJobLoader.java b/spring-batch-core/src/main/java/org/springframework/batch/core/configuration/support/DefaultJobLoader.java
@@ -26,6 +26,7 @@
 import org.jspecify.annotations.NullUnmarked;
 
 import org.springframework.batch.core.job.Job;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.configuration.DuplicateJobException;
 import org.springframework.batch.core.configuration.JobRegistry;
@@ -220,7 +221,8 @@ private Collection<Job> doLoad(ApplicationContextFactory factory, boolean unregi
 	 * @return all the {@link Step} defined by the given step locator and context
 	 * @see StepLocator
 	 */
-	private Collection<Step> getSteps(final StepLocator stepLocator, final ApplicationContext jobApplicationContext) {
+	private Collection<Step> getSteps(final ListableStepLocator stepLocator,
+			final ApplicationContext jobApplicationContext) {
 		final Collection<String> stepNames = stepLocator.getStepNames();
 		final Collection<Step> result = new ArrayList<>();
 		for (String stepName : stepNames) {
@@ -253,7 +255,7 @@ private void doRegister(ConfigurableApplicationContext context, Job job) throws
 		jobRegistry.register(job);
 
 		if (stepRegistry != null) {
-			if (!(job instanceof StepLocator stepLocator)) {
+			if (!(job instanceof ListableStepLocator stepLocator)) {
 				throw new UnsupportedOperationException("Cannot locate steps from a Job that is not a StepLocator: job="
 						+ job.getName() + " does not implement StepLocator");
 			}
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/job/AbstractJob.java b/spring-batch-core/src/main/java/org/springframework/batch/core/job/AbstractJob.java
@@ -37,6 +37,7 @@
 import org.springframework.batch.core.observability.BatchMetrics;
 import org.springframework.batch.core.observability.jfr.events.job.JobExecutionEvent;
 import org.springframework.batch.core.observability.micrometer.MicrometerMetrics;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.step.StepExecution;
 import org.springframework.batch.core.listener.CompositeJobExecutionListener;
@@ -62,7 +63,7 @@
  */
 @NullUnmarked // FIXME to remove once default constructors (required by the batch XML
 				// namespace) are removed
-public abstract class AbstractJob implements Job, StepLocator, BeanNameAware, InitializingBean {
+public abstract class AbstractJob implements Job, ListableStepLocator, BeanNameAware, InitializingBean {
 
 	protected static final Log logger = LogFactory.getLog(AbstractJob.class);
 
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/job/SimpleJob.java b/spring-batch-core/src/main/java/org/springframework/batch/core/job/SimpleJob.java
@@ -24,6 +24,7 @@
 
 import org.springframework.batch.core.BatchStatus;
 
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.step.StepExecution;
 import org.springframework.batch.core.launch.JobRestartException;
@@ -80,7 +81,7 @@ public Collection<String> getStepNames() {
 		for (Step step : steps) {
 			names.add(step.getName());
 
-			if (step instanceof StepLocator stepLocator) {
+			if (step instanceof ListableStepLocator stepLocator) {
 				names.addAll(stepLocator.getStepNames());
 			}
 		}
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/job/flow/FlowJob.java b/spring-batch-core/src/main/java/org/springframework/batch/core/job/flow/FlowJob.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2023 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,6 +24,7 @@
 import org.jspecify.annotations.Nullable;
 import org.springframework.batch.core.job.JobExecution;
 import org.springframework.batch.core.job.JobExecutionException;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.job.AbstractJob;
 import org.springframework.batch.core.job.SimpleStepHandler;
@@ -93,7 +94,7 @@ private void init() {
 	private void findSteps(Flow flow, Map<String, Step> map) {
 
 		for (State state : flow.getStates()) {
-			if (state instanceof StepLocator locator) {
+			if (state instanceof ListableStepLocator locator) {
 				for (String name : locator.getStepNames()) {
 					map.put(name, locator.getStep(name));
 				}
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/job/flow/support/state/StepState.java b/spring-batch-core/src/main/java/org/springframework/batch/core/job/flow/support/state/StepState.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2023 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,6 +20,7 @@
 import java.util.Collection;
 import java.util.List;
 
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.job.flow.FlowExecutionStatus;
 import org.springframework.batch.core.job.flow.FlowExecutor;
@@ -36,7 +37,7 @@
  * @author Mahmoud Ben Hassine
  * @since 2.0
  */
-public class StepState extends AbstractState implements StepLocator, StepHolder {
+public class StepState extends AbstractState implements ListableStepLocator, StepHolder {
 
 	private final Step step;
 
@@ -83,7 +84,7 @@ public Collection<String> getStepNames() {
 
 		names.add(step.getName());
 
-		if (step instanceof StepLocator stepLocator) {
+		if (step instanceof ListableStepLocator stepLocator) {
 			names.addAll(stepLocator.getStepNames());
 		}
 
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/step/ListableStepLocator.java b/spring-batch-core/src/main/java/org/springframework/batch/core/step/ListableStepLocator.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2025-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.batch.core.step;
+
+import java.util.Collection;
+
+/**
+ * Interface for listing {@link Step}s by name.
+ *
+ * @author Mahmoud Ben Hassine
+ * @since 6.0
+ * @see org.springframework.batch.core.step.StepLocator
+ */
+public interface ListableStepLocator extends StepLocator {
+
+	Collection<String> getStepNames();
+
+}
diff --git a/spring-batch-core/src/main/java/org/springframework/batch/core/step/StepLocator.java b/spring-batch-core/src/main/java/org/springframework/batch/core/step/StepLocator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2009 the original author or authors.
+ * Copyright 2009-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,20 +15,17 @@
  */
 package org.springframework.batch.core.step;
 
-import java.util.Collection;
-
 import org.jspecify.annotations.Nullable;
 
 /**
  * Interface for locating a {@link Step} instance by name.
  *
  * @author Dave Syer
+ * @author Mahmoud Ben Hassine
  *
  */
 public interface StepLocator {
 
-	Collection<String> getStepNames();
-
 	@Nullable Step getStep(String stepName);
 
 }
diff --git a/spring-batch-core/src/test/java/org/springframework/batch/core/configuration/support/DefaultJobLoaderTests.java b/spring-batch-core/src/test/java/org/springframework/batch/core/configuration/support/DefaultJobLoaderTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2022 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,12 +25,11 @@
 import org.springframework.batch.core.job.JobExecution;
 import org.springframework.batch.core.job.parameters.JobParametersIncrementer;
 import org.springframework.batch.core.job.parameters.JobParametersValidator;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.configuration.DuplicateJobException;
 import org.springframework.batch.core.configuration.JobRegistry;
 import org.springframework.batch.core.configuration.StepRegistry;
-import org.springframework.batch.core.step.NoSuchStepException;
-import org.springframework.batch.core.step.StepLocator;
 import org.springframework.core.io.ByteArrayResource;
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.test.util.ReflectionTestUtils;
@@ -231,7 +230,7 @@ public boolean isRestartable() {
 
 	}
 
-	public static class StubJob extends BasicStubJob implements StepLocator {
+	public static class StubJob extends BasicStubJob implements ListableStepLocator {
 
 		@Override
 		public Collection<String> getStepNames() {
diff --git a/spring-batch-core/src/test/java/org/springframework/batch/core/configuration/xml/SplitJobParserTests.java b/spring-batch-core/src/test/java/org/springframework/batch/core/configuration/xml/SplitJobParserTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2022 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@
 import org.springframework.batch.core.job.JobInstance;
 import org.springframework.batch.core.job.parameters.JobParameters;
 import org.springframework.batch.core.repository.JobRepository;
-import org.springframework.batch.core.step.StepLocator;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.infrastructure.item.ExecutionContext;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
@@ -58,7 +58,7 @@ void testSplitJob() throws Exception {
 		job.execute(jobExecution);
 		assertEquals(BatchStatus.COMPLETED, jobExecution.getStatus());
 		assertEquals(4, jobExecution.getStepExecutions().size());
-		ArrayList<String> names = new ArrayList<>(((StepLocator) job).getStepNames());
+		ArrayList<String> names = new ArrayList<>(((ListableStepLocator) job).getStepNames());
 		Collections.sort(names);
 		assertEquals("[s1, s2, s3, s4]", names.toString());
 	}
diff --git a/spring-batch-core/src/test/java/org/springframework/batch/core/configuration/xml/StepNameTests.java b/spring-batch-core/src/test/java/org/springframework/batch/core/configuration/xml/StepNameTests.java
@@ -29,7 +29,7 @@
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
 import org.springframework.batch.core.job.Job;
-import org.springframework.batch.core.step.StepLocator;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.parsing.BeanDefinitionParsingException;
 import org.springframework.context.ApplicationContext;
@@ -56,9 +56,9 @@ void testStepNames(Resource resource) throws Exception {
 		if (context == null) {
 			return;
 		}
-		Map<String, StepLocator> stepLocators = context.getBeansOfType(StepLocator.class);
+		Map<String, ListableStepLocator> stepLocators = context.getBeansOfType(ListableStepLocator.class);
 		for (String name : stepLocators.keySet()) {
-			StepLocator stepLocator = stepLocators.get(name);
+			ListableStepLocator stepLocator = stepLocators.get(name);
 			Collection<String> stepNames = stepLocator.getStepNames();
 			Job job = context.getBean(name, Job.class);
 			String jobName = job.getName();
diff --git a/spring-batch-core/src/test/java/org/springframework/batch/core/job/JobSupport.java b/spring-batch-core/src/test/java/org/springframework/batch/core/job/JobSupport.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2023 the original author or authors.
+ * Copyright 2006-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,9 +23,8 @@
 
 import org.springframework.batch.core.job.parameters.DefaultJobParametersValidator;
 import org.springframework.batch.core.job.parameters.JobParametersValidator;
+import org.springframework.batch.core.step.ListableStepLocator;
 import org.springframework.batch.core.step.Step;
-import org.springframework.batch.core.step.NoSuchStepException;
-import org.springframework.batch.core.step.StepLocator;
 import org.springframework.beans.factory.BeanNameAware;
 import org.springframework.util.ClassUtils;
 
@@ -38,7 +37,7 @@
  * @author Dave Syer
  * @author Mahmoud Ben Hassine
  */
-public class JobSupport implements BeanNameAware, Job, StepLocator {
+public class JobSupport implements BeanNameAware, Job, ListableStepLocator {
 
 	private final Map<String, Step> steps = new HashMap<>();
 
diff --git a/spring-batch-integration/src/main/java/org/springframework/batch/integration/partition/BeanFactoryStepLocator.java b/spring-batch-integration/src/main/java/org/springframework/batch/integration/partition/BeanFactoryStepLocator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2009-2023 the original author or authors.
+ * Copyright 2009-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,20 +15,15 @@
  */
 package org.springframework.batch.integration.partition;
 
-import java.util.Arrays;
-import java.util.Collection;
-
 import org.springframework.batch.core.step.Step;
 import org.springframework.batch.core.step.StepLocator;
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
-import org.springframework.beans.factory.ListableBeanFactory;
-import org.springframework.util.Assert;
 
 /**
  * A {@link StepLocator} implementation that just looks in its enclosing bean factory for
- * components of type {@link Step}.
+ * {@link Step}s by name.
  *
  * @author Dave Syer
  * @author Mahmoud Ben Hassine
@@ -52,15 +47,4 @@ public Step getStep(String stepName) {
 		return beanFactory.getBean(stepName, Step.class);
 	}
 
-	/**
-	 * Look in the bean factory for all beans of type {@link Step}.
-	 * @throws IllegalStateException if the {@link BeanFactory} is not listable
-	 * @see StepLocator#getStepNames()
-	 */
-	@Override
-	public Collection<String> getStepNames() {
-		Assert.state(beanFactory instanceof ListableBeanFactory, "BeanFactory is not listable.");
-		return Arrays.asList(((ListableBeanFactory) beanFactory).getBeanNamesForType(Step.class));
-	}
-
 }
diff --git a/spring-batch-integration/src/test/java/org/springframework/batch/integration/partition/BeanFactoryStepLocatorTests.java b/spring-batch-integration/src/test/java/org/springframework/batch/integration/partition/BeanFactoryStepLocatorTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2009-2023 the original author or authors.
+ * Copyright 2009-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,7 +15,6 @@
  */
 package org.springframework.batch.integration.partition;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 import org.junit.jupiter.api.Test;
@@ -37,14 +36,6 @@ void testGetStep() {
 		assertNotNull(stepLocator.getStep("foo"));
 	}
 
-	@Test
-	void testGetStepNames() {
-		beanFactory.registerSingleton("foo", new StubStep("foo"));
-		beanFactory.registerSingleton("bar", new StubStep("bar"));
-		stepLocator.setBeanFactory(beanFactory);
-		assertEquals(2, stepLocator.getStepNames().size());
-	}
-
 	private static final class StubStep implements Step {
 
 		private final String name;

Original file line number	Diff line number	Diff line change
`@@ -24,6 +24,7 @@`
`24`	`24`
`25`	`25`	`import org.springframework.batch.core.BatchStatus;`
`26`	`26`
	`27`	`+import org.springframework.batch.core.step.ListableStepLocator;`
`27`	`28`	`import org.springframework.batch.core.step.Step;`
`28`	`29`	`import org.springframework.batch.core.step.StepExecution;`
`29`	`30`	`import org.springframework.batch.core.launch.JobRestartException;`
`@@ -80,7 +81,7 @@ public Collection<String> getStepNames() {`
`80`	`81`	`for (Step step : steps) {`
`81`	`82`	`names.add(step.getName());`
`82`	`83`
`83`		`- if (step instanceof StepLocator stepLocator) {`
	`84`	`+ if (step instanceof ListableStepLocator stepLocator) {`
`84`	`85`	`names.addAll(stepLocator.getStepNames());`
`85`	`86`	`}`
`86`	`87`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1,5 +1,5 @@`
`1`	`1`	`/*`
`2`		`- * Copyright 2009 the original author or authors.`
	`2`	`+ * Copyright 2009-2025 the original author or authors.`
`3`	`3`	`*`
`4`	`4`	`* Licensed under the Apache License, Version 2.0 (the "License");`
`5`	`5`	`* you may not use this file except in compliance with the License.`
`@@ -15,20 +15,17 @@`
`15`	`15`	`*/`
`16`	`16`	`package org.springframework.batch.core.step;`
`17`	`17`
`18`		`-import java.util.Collection;`
`19`		`-`
`20`	`18`	`import org.jspecify.annotations.Nullable;`
`21`	`19`
`22`	`20`	`/**`
`23`	`21`	`* Interface for locating a {@link Step} instance by name.`
`24`	`22`	`*`
`25`	`23`	`* @author Dave Syer`
	`24`	`+ * @author Mahmoud Ben Hassine`
`26`	`25`	`*`
`27`	`26`	`*/`
`28`	`27`	`public interface StepLocator {`
`29`	`28`
`30`		`- Collection<String> getStepNames();`
`31`		`-`
`32`	`29`	`@Nullable Step getStep(String stepName);`
`33`	`30`
`34`	`31`	`}`