testdocboost.java

Lucene a java open-source SearchEngine Framework

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 org.apache.lucene.util.LuceneTestCase;
import org.apache.lucene.analysis.SimpleAnalyzer;
import org.apache.lucene.document.*;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.Term;
import org.apache.lucene.store.RAMDirectory;

/** Document boost unit test.
 *
 *
 * @version $Revision: 583534 $
 */
public class TestDocBoost extends LuceneTestCase {
  public TestDocBoost(String name) {
    super(name);
  }

  public void testDocBoost() throws Exception {
    RAMDirectory store = new RAMDirectory();
    IndexWriter writer = new IndexWriter(store, new SimpleAnalyzer(), true);

    Fieldable f1 = new Field("field", "word", Field.Store.YES, Field.Index.TOKENIZED);
    Fieldable f2 = new Field("field", "word", Field.Store.YES, Field.Index.TOKENIZED);
    f2.setBoost(2.0f);

    Document d1 = new Document();
    Document d2 = new Document();
    Document d3 = new Document();
    Document d4 = new Document();
    d3.setBoost(3.0f);
    d4.setBoost(2.0f);

    d1.add(f1);                                 // boost = 1
    d2.add(f2);                                 // boost = 2
    d3.add(f1);                                 // boost = 3
    d4.add(f2);                                 // boost = 4

    writer.addDocument(d1);
    writer.addDocument(d2);
    writer.addDocument(d3);
    writer.addDocument(d4);
    writer.optimize();
    writer.close();

    final float[] scores = new float[4];

    new IndexSearcher(store).search
      (new TermQuery(new Term("field", "word")),
       new HitCollector() {
         public final void collect(int doc, float score) {
           scores[doc] = score;
         }
       });

    float lastScore = 0.0f;

    for (int i = 0; i < 4; i++) {
      assertTrue(scores[i] > lastScore);
      lastScore = scores[i];
    }
  }
}