/*
* Copyright 2002-2005 the original author or authors.
*
* Licensed 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.springmodules.lucene.search.core;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.queryParser.MultiFieldQueryParser;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.Query;
/**
* Callback class for creating a Query for Lucene search basing the
* Lucene QueryParser and MultiFieldQueryParser classes.
*
* <p>Used for input Query creation in LuceneSearchTemplate. Alternatively,
* Query instances can be passed into LuceneSearchTemplate's corresponding
* <code>search</code> methods directly.
*
* @author Thierry Templier
* @see org.springmodules.lucene.search.query.QueryCreator
*/
public abstract class ParsedQueryCreator implements QueryCreator {
/**
* This method constructs a Lucene query using the Lucene
* Analyzer class and the Lucene QueryParser or MultiFieldQueryParser
* class according the params of the query returned by the configureQuery
* method.
* @param analyzer the Lucene Analyzer to use
* @return the constructed Query
* @throws ParseException if thrown by a Lucene method, to be auto-converted
* to a LuceneSearchException
* @see #configureQuery()
*/
public final Query createQuery(Analyzer analyzer) throws ParseException {
QueryParams params=configureQuery();
String[] tokens=params.getToken();
Query query=null;
if( tokens.length==1 ) {
QueryParser parser=new QueryParser(tokens[0],analyzer);
query=parser.parse(params.getTextToSearch());
} else {
query=MultiFieldQueryParser.parse(params.getTextToSearch(),tokens,analyzer);
}
setQueryProperties(query);
return query;
}
/**
* Subclasses must implement this method to configure with an instance
* of QueryParams which must contains informations about the tokens
* and the text to search.
* @return the parameters to construct a Query
*/
public abstract QueryParams configureQuery();
/**
* Subclasses must overwrite this method to specify properties on the
* constructed query.
* @param query the constructed Query
*/
protected void setQueryProperties(Query query) {
}
/**
* This bean is used to contain the parameters needed to construct
* a query with a query parser.
*/
public static class QueryParams {
private String[] token;
private String textToSearch;
public QueryParams(String token,String textToSearch) {
this.token=new String[1];
this.token[0]=token;
this.textToSearch=textToSearch;
}
public QueryParams(String[] token,String textToSearch) {
this.token=token;
this.textToSearch=textToSearch;
}
public String[] getToken() {
return token;
}
public String getTextToSearch() {
return textToSearch;
}
}
}