package org.apache.lucene.search.similar;
/**
* 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.io.StringReader;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriter.MaxFieldLength;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.LuceneTestCase;
public class TestMoreLikeThis extends LuceneTestCase {
private RAMDirectory directory;
private IndexReader reader;
private IndexSearcher searcher;
@Override
protected void setUp() throws Exception {
directory = new RAMDirectory();
IndexWriter writer = new IndexWriter(directory, new StandardAnalyzer(org.apache.lucene.util.Version.LUCENE_CURRENT),
true, MaxFieldLength.UNLIMITED);
// Add series of docs with specific information for MoreLikeThis
addDoc(writer, "lucene");
addDoc(writer, "lucene release");
writer.close();
reader = IndexReader.open(directory, true);
searcher = new IndexSearcher(reader);
}
@Override
protected void tearDown() throws Exception {
reader.close();
searcher.close();
directory.close();
}
private void addDoc(IndexWriter writer, String text) throws IOException {
Document doc = new Document();
doc.add(new Field("text", text, Field.Store.YES, Field.Index.ANALYZED));
writer.addDocument(doc);
}
public void testBoostFactor() throws Throwable {
Map originalValues = getOriginalValues();
MoreLikeThis mlt = new MoreLikeThis(
reader);
mlt.setMinDocFreq(1);
mlt.setMinTermFreq(1);
mlt.setMinWordLen(1);
mlt.setFieldNames(new String[] { "text" });
mlt.setBoost(true);
// this mean that every term boost factor will be multiplied by this
// number
float boostFactor = 5;
mlt.setBoostFactor(boostFactor);
BooleanQuery query = (BooleanQuery) mlt.like(new StringReader(
"lucene release"));
List clauses = query.clauses();
assertEquals("Expected " + originalValues.size() + " clauses.",
originalValues.size(), clauses.size());
for (int i = 0; i < clauses.size(); i++) {
BooleanClause clause = (BooleanClause) clauses.get(i);
TermQuery tq = (TermQuery) clause.getQuery();
Float termBoost = (Float) originalValues.get(tq.getTerm().text());
assertNotNull("Expected term " + tq.getTerm().text(), termBoost);
float totalBoost = termBoost.floatValue() * boostFactor;
assertEquals("Expected boost of " + totalBoost + " for term '"
+ tq.getTerm().text() + "' got " + tq.getBoost(),
totalBoost, tq.getBoost(), 0.0001);
}
}
private Map getOriginalValues() throws IOException {
Map originalValues = new HashMap();
MoreLikeThis mlt = new MoreLikeThis(reader);
mlt.setMinDocFreq(1);
mlt.setMinTermFreq(1);
mlt.setMinWordLen(1);
mlt.setFieldNames(new String[] { "text" });
mlt.setBoost(true);
BooleanQuery query = (BooleanQuery) mlt.like(new StringReader(
"lucene release"));
List clauses = query.clauses();
for (int i = 0; i < clauses.size(); i++) {
BooleanClause clause = (BooleanClause) clauses.get(i);
TermQuery tq = (TermQuery) clause.getQuery();
originalValues.put(tq.getTerm().text(), Float.valueOf(tq.getBoost()));
}
return originalValues;
}
}