searchingfrommanyindexes.SearchingFromManyIndexes.java Source code

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Here is the source code for searchingfrommanyindexes.SearchingFromManyIndexes.java

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package searchingfrommanyindexes;

import static junit.framework.Assert.assertEquals;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.WhitespaceAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.MultiSearcher;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermRangeQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.search.TopScoreDocCollector;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;

/**
 *
 * @author christones
 */
public class SearchingFromManyIndexes {
    private static IndexSearcher[] searchers;

    /**
     * @param args the command line arguments
     * @throws java.lang.Exception
     */
    public static void main(String[] args) throws Exception {
        // TODO code application logic here
        SearchingFromManyIndexes.setUp();
        SearchingFromManyIndexes.testMulti();
    }

    public static void setUp() throws Exception {
        String[] animals = { "aardvark", "beaver", "coati", "dog", "elephant", "frog", "gila monster", "horse",
                "iguana", "javelina", "kangaroo", "lemur", "moose", "nematode", "orca", "python", "quokka", "rat",
                "scorpion", "tarantula", "uromastyx", "vicuna", "walrus", "xiphias", "yak", "zebra" };
        Analyzer analyzer = new WhitespaceAnalyzer();
        /*Create two
        directories*/
        Directory aTOmDirectory = new RAMDirectory();
        Directory nTOzDirectory = new RAMDirectory();

        IndexWriter nTOzWriter;
        try (IndexWriter aTOmWriter = new IndexWriter(aTOmDirectory, analyzer,
                IndexWriter.MaxFieldLength.UNLIMITED)) {
            nTOzWriter = new IndexWriter(nTOzDirectory, analyzer, IndexWriter.MaxFieldLength.UNLIMITED);
            for (int i = animals.length - 1; i >= 0; i--) {
                Document doc = new Document();
                String animal = animals[i];
                doc.add(new Field("animal", animal, Field.Store.YES, Field.Index.NOT_ANALYZED));
                if (animal.charAt(0) < 'n') {
                    aTOmWriter.addDocument(doc);
                    //Index halves of
                } else {
                    //the alphabet
                    nTOzWriter.addDocument(doc);
                }
            }
        }
        nTOzWriter.close();

        searchers = new IndexSearcher[2];
        searchers[0] = new IndexSearcher(aTOmDirectory);
        searchers[1] = new IndexSearcher(nTOzDirectory);
    }

    public static void testMulti() throws Exception {
        MultiSearcher searcher = new MultiSearcher(searchers);
        TermRangeQuery query = new TermRangeQuery("animal", "h", "t", true, true);

        //Search both indexesLeveraging term vectors
        // Ranker
        TopScoreDocCollector collector = TopScoreDocCollector.create(10, true);
        TopDocs hits = searcher.search(query, 10);
        assertEquals("tarantula not included", 12, hits.totalHits);
        // Display results
        System.out.println("Found " + hits.scoreDocs.length + " hits.");
        for (int i = 0; i < hits.totalHits; ++i) {
            Document d = searcher.doc(i + 1);
            System.out.println((i + 1) + ". " + d.get("animal"));
        }
        // Close the multi searcher

    }
}