LuceneSearcherTest.java

package test.lucene;

import static org.testng.Assert.assertNotNull;

import java.io.IOException;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.LowerCaseFilter;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.Tokenizer;
import org.apache.lucene.analysis.core.WhitespaceTokenizer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.queryparser.classic.ParseException;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.SearcherFactory;
import org.apache.lucene.search.SearcherManager;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.RAMDirectory;
import org.testng.Assert;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

/**
 * @author Florent Benoit
 */
public class LuceneSearcherTest {

  private static final String NAME_FIELD = "name";
  private IndexWriter luceneIndexWriter;
  private RAMDirectory ramDirectory;
  private DirectoryReader luceneIndexReader;
  private SearcherManager searcherManager;

  @BeforeMethod
  public void init() throws IOException {
    ramDirectory = new RAMDirectory();
    luceneIndexWriter = new IndexWriter(ramDirectory, new IndexWriterConfig(makeAnalyzer()));
  }

  protected void addFile(String name) throws IOException {
    final Document doc = new Document();
    doc.add(new TextField(NAME_FIELD, name, Field.Store.YES));
    luceneIndexWriter.addDocument(doc);
    luceneIndexWriter.commit();
  }

  protected Analyzer makeAnalyzer() {
    return new Analyzer() {
      @Override
      protected TokenStreamComponents createComponents(String fieldName) {
        Tokenizer tokenizer = new WhitespaceTokenizer();
        TokenStream filter = new LowerCaseFilter(tokenizer);
        return new TokenStreamComponents(tokenizer, filter);
      }
    };
  }


  protected long search(String name) throws IOException, ParseException {
    luceneIndexReader = DirectoryReader.open(luceneIndexWriter.getDirectory());
    searcherManager = new SearcherManager(luceneIndexWriter, new SearcherFactory());

    IndexSearcher indexSearcher = searcherManager.acquire();
    Query luceneQuery = createLuceneQuery(name);
    TopDocs topDocs = indexSearcher.search(luceneQuery, 100);
    assertNotNull(topDocs);
    return topDocs.totalHits;

  }

  private Query createLuceneQuery(String name) throws ParseException {
    BooleanQuery.Builder luceneQueryBuilder = new BooleanQuery.Builder();
    QueryParser qParser = new QueryParser(NAME_FIELD, makeAnalyzer());
    luceneQueryBuilder.add(qParser.parse(name), BooleanClause.Occur.MUST);
    BooleanQuery booleanQuery = luceneQueryBuilder.build();
    System.out.println("Query: " + booleanQuery.toString());
    return booleanQuery;
  }



  @DataProvider
  public Object[][] searchByName() {
    return new Object[][] {
        {"prefixFileName.txt", "prefixF*"},
        {"prefixFileName.txt", "prefix*"},
        {"name.with.dot.txt", "name.With.Dot.txt"},
        {"sameName.txt", "sameName.txt"},
        {"notCaseSensitive.txt", "notcasesensitive.txt"},
        {"fullName.txt", "full*"},
        {"file name.txt", "file name"},
    };
  }

  @Test(dataProvider = "searchByName")
  public void searchFileByName(String fileName, String searchedFileName) throws Exception {

    // first, add the file
    addFile(fileName);

    // then search
    long result = search(searchedFileName);
    Assert.assertEquals(result, 1, "Invalid number when searching file named '" + searchedFileName + "' while filename was '" + fileName + "'.");

  }

}