Lucene example source code file (TestBooleanScorer.java)

This example Lucene source code file (TestBooleanScorer.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lucene tags/keywords

booleanquery, booleanquery, booleanscorer, io, ioexception, ioexception, no_more_docs, override, override, randomindexwriter, scorer, string, term, termquery, termquery, util

The Lucene TestBooleanScorer.java source code

package org.apache.lucene.search;

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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
 *
 *     http://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.
 */

import java.io.IOException;
import java.util.Arrays;

import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.RandomIndexWriter;
import org.apache.lucene.index.Term;
import org.apache.lucene.store.Directory;

import org.apache.lucene.util.LuceneTestCase;

public class TestBooleanScorer extends LuceneTestCase
{
  private static final String FIELD = "category";
  
  public void testMethod() throws Exception {
    Directory directory = newDirectory();

    String[] values = new String[] { "1", "2", "3", "4" };

    RandomIndexWriter writer = new RandomIndexWriter(random, directory);
    for (int i = 0; i < values.length; i++) {
      Document doc = new Document();
      doc.add(newField(FIELD, values[i], Field.Store.YES, Field.Index.NOT_ANALYZED));
      writer.addDocument(doc);
    }
    IndexReader ir = writer.getReader();
    writer.close();

    BooleanQuery booleanQuery1 = new BooleanQuery();
    booleanQuery1.add(new TermQuery(new Term(FIELD, "1")), BooleanClause.Occur.SHOULD);
    booleanQuery1.add(new TermQuery(new Term(FIELD, "2")), BooleanClause.Occur.SHOULD);

    BooleanQuery query = new BooleanQuery();
    query.add(booleanQuery1, BooleanClause.Occur.MUST);
    query.add(new TermQuery(new Term(FIELD, "9")), BooleanClause.Occur.MUST_NOT);

    IndexSearcher indexSearcher = newSearcher(ir);
    ScoreDoc[] hits = indexSearcher.search(query, null, 1000).scoreDocs;
    assertEquals("Number of matched documents", 2, hits.length);
    indexSearcher.close();
    ir.close();
    directory.close();
  }
  
  public void testEmptyBucketWithMoreDocs() throws Exception {
    // This test checks the logic of nextDoc() when all sub scorers have docs
    // beyond the first bucket (for example). Currently, the code relies on the
    // 'more' variable to work properly, and this test ensures that if the logic
    // changes, we have a test to back it up.
    
    Similarity sim = Similarity.getDefault();
    Scorer[] scorers = new Scorer[] {new Scorer(sim) {
      private int doc = -1;
      @Override public float score() throws IOException { return 0; }
      @Override public int docID() { return doc; }
      
      @Override public int nextDoc() throws IOException {
        return doc = doc == -1 ? 3000 : NO_MORE_DOCS;
      }

      @Override public int advance(int target) throws IOException {
        return doc = target <= 3000 ? 3000 : NO_MORE_DOCS;
      }
      
    }};
    BooleanScorer bs = new BooleanScorer(null, false, sim, 1, Arrays.asList(scorers), null, scorers.length);
    
    assertEquals("should have received 3000", 3000, bs.nextDoc());
    assertEquals("should have received NO_MORE_DOCS", DocIdSetIterator.NO_MORE_DOCS, bs.nextDoc());
  }

}