/*
* 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.
*/
package org.apache.jackrabbit.core.query.lucene;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.TermDocs;
import org.apache.lucene.analysis.Analyzer;
import java.io.IOException;
/**
* <code>SimilarityQuery</code> implements a query that returns similar nodes
* for a given node UUID.
*/
public class SimilarityQuery extends Query {
/**
* The UUID of the node for which to find similar nodes.
*/
private final String uuid;
/**
* The analyzer in use.
*/
private final Analyzer analyzer;
public SimilarityQuery(String uuid, Analyzer analyzer) {
this.uuid = uuid;
this.analyzer = analyzer;
}
/**
* {@inheritDoc}
*/
public Query rewrite(IndexReader reader) throws IOException {
MoreLikeThis more = new MoreLikeThis(reader);
more.setAnalyzer(analyzer);
more.setFieldNames(new String[]{FieldNames.FULLTEXT});
more.setMinWordLen(4);
Query similarityQuery = null;
TermDocs td = reader.termDocs(TermFactory.createUUIDTerm(uuid));
try {
if (td.next()) {
similarityQuery = more.like(td.doc());
}
} finally {
td.close();
}
if (similarityQuery != null) {
return similarityQuery.rewrite(reader);
} else {
// return dummy query that never matches
return new BooleanQuery();
}
}
/**
* {@inheritDoc}
*/
public String toString(String field) {
return "rep:similar(" + uuid + ")";
}
}