FullTextSearchOnS3.java

/*
 * The following code is open to all
 *aIt is merely an explanation of using Lucene with S3
 * and have been borrowed from their respective code samples
 * 1.  git clone https://github.com/EMCECS/ecs-samples.git
 * 2.  git clone https://github.com/macluq/helloLucene
 */
package FullTextSearchOnS3;

import java.io.IOException;
import java.text.ParseException;

import com.emc.object.s3.S3Client;
import com.emc.object.s3.S3ObjectMetadata;
import com.emc.object.s3.request.PutObjectRequest;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopScoreDocCollector;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;

public class FullTextSearchOnS3 {

        public static void main(String[] args) throws IOException, ParseException {
                // 0. Specify the analyzer for tokenizing text.
                //    The same analyzer should be used for indexing and searching
                StandardAnalyzer analyzer = new StandardAnalyzer(Version.LUCENE_40);

                // 1. create the index
                Directory index = new RAMDirectory();

                IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_40, analyzer);

                IndexWriter w = new IndexWriter(index, config);
                addDoc(w, "Lucene in Action", "193398817");
                addDoc(w, "Lucene for Dummies", "55320055Z");
                addDoc(w, "Managing Gigabytes", "55063554A");
                addDoc(w, "The Art of Computer Science", "9900333X");
                w.close();

                // 2. query
                String querystr = args.length > 0 ? args[0] : "lucene";

                // the "title" arg specifies the default field to use
                // when no field is explicitly specified in the query.
               Query q = null;
                try {
                        q = new QueryParser(Version.LUCENE_40, "title", analyzer).parse(querystr);
                } catch (org.apache.lucene.queryparser.classic.ParseException e) {
                        e.printStackTrace();
                }

                // 3. search
                int hitsPerPage = 10;
                IndexReader reader = DirectoryReader.open(index);
                IndexSearcher searcher = new IndexSearcher(reader);
                TopScoreDocCollector collector = TopScoreDocCollector.create(hitsPerPage, true);
                searcher.search(q, collector);
                ScoreDoc[] hits = collector.topDocs().scoreDocs;

                // 4. display results
                System.out.println("Found " + hits.length + " hits.");
                for (int i = 0; i < hits.length; ++i) {
                        int docId = hits[i].doc;
                        Document d = searcher.doc(docId);
                        System.out.println((i + 1) + ". " + d.get("isbn") + "\t" + d.get("title"));
                }

                // reader can only be closed when there
                // is no need to access the documents any more.
                reader.close();
        }

        private static void addDoc(IndexWriter w, String title, String isbn) throws IOException {
                Document doc = new Document();
                doc.add(new TextField("title", title, Field.Store.YES));

                // use a string field for isbn because we don't want it tokenized
                doc.add(new StringField("isbn", isbn, Field.Store.YES));
                putS3(isbn, doc.toString(), "title", title);
                w.addDocument(doc);
        }

        private static void putS3(String key, String content, String metaKey, String metaValue) {
                try {
                    S3Client s3 = ECSS3Factory.getS3Client();
                    S3ObjectMetadata metadata = new S3ObjectMetadata();
                    metadata.addUserMetadata(metaKey, metaValue);
                    PutObjectRequest req = new PutObjectRequest(ECSS3Factory.S3_BUCKET, key, content).withObjectMetadata(metadata);
                    s3.putObject(req);

                    // print out object key/value and metadata key/value for validation
                    System.out.println( String.format("created object [%s/%s] with metadata [%s=%s] and content: [%s]",
                    ECSS3Factory.S3_BUCKET, key, metaKey, metaValue, content))
                } catch (Exception e) {
                    e.printStackTrace();
                }
        }
}