package org.apache.lucene.xmlparser.builders;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.Query;
import org.apache.lucene.xmlparser.DOMUtils;
import org.apache.lucene.xmlparser.ParserException;
import org.apache.lucene.xmlparser.QueryBuilder;
import org.w3c.dom.Element;
import org.apache.lucene.util.Version;
/**
* 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.
*/
/**
* UserInputQueryBuilder uses 1 of 2 strategies for thread-safe parsing:
* 1) Synchronizing access to "parse" calls on a previously supplied QueryParser
* or..
* 2) creating a new QueryParser object for each parse request
*/
public class UserInputQueryBuilder implements QueryBuilder {
QueryParser unSafeParser;
private Analyzer analyzer;
private String defaultField;
/**
* This constructor has the disadvantage of not being able to change choice of default field name
* @param parser thread un-safe query parser
*/
public UserInputQueryBuilder(QueryParser parser) {
this.unSafeParser = parser;
}
public UserInputQueryBuilder(String defaultField, Analyzer analyzer) {
this.analyzer = analyzer;
this.defaultField = defaultField;
}
/* (non-Javadoc)
* @see org.apache.lucene.xmlparser.QueryObjectBuilder#process(org.w3c.dom.Element)
*/
public Query getQuery(Element e) throws ParserException {
String text=DOMUtils.getText(e);
try {
Query q = null;
if(unSafeParser!=null)
{
//synchronize on unsafe parser
synchronized (unSafeParser)
{
q = unSafeParser.parse(text);
}
}
else
{
String fieldName=DOMUtils.getAttribute(e, "fieldName", defaultField);
//Create new parser
QueryParser parser=createQueryParser(fieldName, analyzer);
q = parser.parse(text);
}
q.setBoost(DOMUtils.getAttribute(e,"boost",1.0f));
return q;
} catch (ParseException e1) {
throw new ParserException(e1.getMessage());
}
}
/**
* Method to create a QueryParser - designed to be overridden
* @param fieldName
* @param analyzer
* @return QueryParser
*/
protected QueryParser createQueryParser(String fieldName, Analyzer analyzer)
{
return new QueryParser(Version.LUCENE_CURRENT, fieldName,analyzer);
}
}