luceneexample.LuceneExample.java Source code

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Here is the source code for luceneexample.LuceneExample.java

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/*
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package luceneexample;

/**
 *
 * @author TienDV
 */
import java.io.File;
import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

public class LuceneExample {

    String indexDir = "D:\\Codes\\Lucene\\textscreen\\index";
    String dataDir = "D:\\Codes\\Lucene\\textscreen\\text";
    Indexer indexer;
    Searcher searcher;

    public static void main(String[] args) throws IOException, ParseException {
        LuceneExample tester;
        tester = new LuceneExample();
        //  String indexDir = "D:\\Codes\\Lucene\\index";
        // tester.searchInDirectory(indexDir, "a person holding a knife");
        try {
            tester = new LuceneExample();
            tester.createIndex();
            tester.search("news");
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }

    private void createIndex() throws IOException {
        indexer = new Indexer(indexDir);
        int numIndexed;
        long startTime = System.currentTimeMillis();
        numIndexed = indexer.createIndex(dataDir, new TextFileFilter());
        long endTime = System.currentTimeMillis();
        indexer.close();
        System.out.println(numIndexed + " File indexed, time taken: " + (endTime - startTime) + " ms");
    }

    private void search(String searchQuery) throws IOException, ParseException {
        searcher = new Searcher(indexDir);
        long startTime = System.currentTimeMillis();
        TopDocs hits = searcher.search(searchQuery);
        long endTime = System.currentTimeMillis();

        System.out.println(hits.totalHits + " documents found. Time :" + (endTime - startTime));
        for (ScoreDoc scoreDoc : hits.scoreDocs) {
            Document doc = searcher.getDocument(scoreDoc);
            System.out.println("File: " + doc.get(LuceneConstants.FILE_NAME));
        }
        searcher.close();
    }

    private void searchInDirectory(String indexDirectory, String queryString) throws IOException, ParseException {

        System.out.println("Searching for '" + queryString + "'");
        File pathIndexDir = new File(indexDirectory);
        Directory index = FSDirectory.open(pathIndexDir);
        IndexReader reader = IndexReader.open(index);
        IndexSearcher searcher = new IndexSearcher(reader);
        QueryParser queryParser = new QueryParser(Version.LUCENE_36, LuceneConstants.CONTENTS,
                new StandardAnalyzer(Version.LUCENE_36));
        Query query = queryParser.parse(queryString);
        TopDocs tops = searcher.search(query, 30);
        ScoreDoc[] scoreDoc = tops.scoreDocs;
        System.out.println(scoreDoc.length);
        for (ScoreDoc score : scoreDoc) {
            //    System.out.println("DOC " + score.doc + " SCORE " + score.score);
            Document doc = searcher.doc(score.doc);
            System.out.println("File: " + doc.get(LuceneConstants.FILE_NAME));
            searcher.close();
        }
    }

}