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.Random;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.RandomIndexWriter;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.LuceneTestCase;
public class TestTopDocsCollector extends LuceneTestCase {
private static final class MyTopsDocCollector extends TopDocsCollector<ScoreDoc> {
private int idx = 0;
private int base = 0;
public MyTopsDocCollector(int size) {
super(new HitQueue(size, false));
}
@Override
protected TopDocs newTopDocs(ScoreDoc[] results, int start) {
if (results == null) {
return EMPTY_TOPDOCS;
}
float maxScore = Float.NaN;
if (start == 0) {
maxScore = results[0].score;
} else {
for (int i = pq.size(); i > 1; i--) { pq.pop(); }
maxScore = pq.pop().score;
}
return new TopDocs(totalHits, results, maxScore);
}
@Override
public void collect(int doc) throws IOException {
++totalHits;
pq.insertWithOverflow(new ScoreDoc(doc + base, scores[idx++]));
}
@Override
public void setNextReader(IndexReader reader, int docBase)
throws IOException {
base = docBase;
}
@Override
public void setScorer(Scorer scorer) throws IOException {
// Don't do anything. Assign scores in random
}
@Override
public boolean acceptsDocsOutOfOrder() {
return true;
}
}
// Scores array to be used by MyTopDocsCollector. If it is changed, MAX_SCORE
// must also change.
private static final float[] scores = new float[] {
0.7767749f, 1.7839992f, 8.9925785f, 7.9608946f, 0.07948637f, 2.6356435f,
7.4950366f, 7.1490803f, 8.108544f, 4.961808f, 2.2423935f, 7.285586f, 4.6699767f,
2.9655676f, 6.953706f, 5.383931f, 6.9916306f, 8.365894f, 7.888485f, 8.723962f,
3.1796896f, 0.39971232f, 1.3077754f, 6.8489285f, 9.17561f, 5.060466f, 7.9793315f,
8.601509f, 4.1858315f, 0.28146625f
};
private static final float MAX_SCORE = 9.17561f;
private Directory dir;
private IndexReader reader;
private TopDocsCollector<ScoreDoc> doSearch(int numResults) throws IOException {
Query q = new MatchAllDocsQuery();
IndexSearcher searcher = new IndexSearcher(reader);
TopDocsCollector<ScoreDoc> tdc = new MyTopsDocCollector(numResults);
searcher.search(q, tdc);
searcher.close();
return tdc;
}
@Override
protected void setUp() throws Exception {
super.setUp();
// populate an index with 30 documents, this should be enough for the test.
// The documents have no content - the test uses MatchAllDocsQuery().
Random random = newRandom();
dir = newDirectory(random);
RandomIndexWriter writer = new RandomIndexWriter(random, dir);
for (int i = 0; i < 30; i++) {
writer.addDocument(new Document());
}
reader = writer.getReader();
writer.close();
}
@Override
protected void tearDown() throws Exception {
reader.close();
dir.close();
dir = null;
super.tearDown();
}
public void testInvalidArguments() throws Exception {
int numResults = 5;
TopDocsCollector<ScoreDoc> tdc = doSearch(numResults);
// start < 0
assertEquals(0, tdc.topDocs(-1).scoreDocs.length);
// start > pq.size()
assertEquals(0, tdc.topDocs(numResults + 1).scoreDocs.length);
// start == pq.size()
assertEquals(0, tdc.topDocs(numResults).scoreDocs.length);
// howMany < 0
assertEquals(0, tdc.topDocs(0, -1).scoreDocs.length);
// howMany == 0
assertEquals(0, tdc.topDocs(0, 0).scoreDocs.length);
}
public void testZeroResults() throws Exception {
TopDocsCollector<ScoreDoc> tdc = new MyTopsDocCollector(5);
assertEquals(0, tdc.topDocs(0, 1).scoreDocs.length);
}
public void testFirstResultsPage() throws Exception {
TopDocsCollector<ScoreDoc> tdc = doSearch(15);
assertEquals(10, tdc.topDocs(0, 10).scoreDocs.length);
}
public void testSecondResultsPages() throws Exception {
TopDocsCollector<ScoreDoc> tdc = doSearch(15);
// ask for more results than are available
assertEquals(5, tdc.topDocs(10, 10).scoreDocs.length);
// ask for 5 results (exactly what there should be
tdc = doSearch(15);
assertEquals(5, tdc.topDocs(10, 5).scoreDocs.length);
// ask for less results than there are
tdc = doSearch(15);
assertEquals(4, tdc.topDocs(10, 4).scoreDocs.length);
}
public void testGetAllResults() throws Exception {
TopDocsCollector<ScoreDoc> tdc = doSearch(15);
assertEquals(15, tdc.topDocs().scoreDocs.length);
}
public void testGetResultsFromStart() throws Exception {
TopDocsCollector<ScoreDoc> tdc = doSearch(15);
// should bring all results
assertEquals(15, tdc.topDocs(0).scoreDocs.length);
tdc = doSearch(15);
// get the last 5 only.
assertEquals(5, tdc.topDocs(10).scoreDocs.length);
}
public void testMaxScore() throws Exception {
// ask for all results
TopDocsCollector<ScoreDoc> tdc = doSearch(15);
TopDocs td = tdc.topDocs();
assertEquals(MAX_SCORE, td.getMaxScore(), 0f);
// ask for 5 last results
tdc = doSearch(15);
td = tdc.topDocs(10);
assertEquals(MAX_SCORE, td.getMaxScore(), 0f);
}
// This does not test the PQ's correctness, but whether topDocs()
// implementations return the results in decreasing score order.
public void testResultsOrder() throws Exception {
TopDocsCollector<ScoreDoc> tdc = doSearch(15);
ScoreDoc[] sd = tdc.topDocs().scoreDocs;
assertEquals(MAX_SCORE, sd[0].score, 0f);
for (int i = 1; i < sd.length; i++) {
assertTrue(sd[i - 1].score >= sd[i].score);
}
}
}