/**
* Copyright 2014 National University of Ireland, Galway.
*
* This file is part of the SIREn project. Project and contact information:
*
* https://github.com/rdelbru/SIREn
*
* 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.sindice.siren.qparser.keyword.builders;
import org.apache.lucene.queryparser.flexible.core.QueryNodeException;
import org.apache.lucene.queryparser.flexible.core.builders.QueryTreeBuilder;
import org.apache.lucene.queryparser.flexible.core.nodes.BoostQueryNode;
import org.apache.lucene.queryparser.flexible.core.nodes.QueryNode;
import org.apache.lucene.search.Query;
/**
* This builder basically reads the {@link Query} object set on the
* {@link BoostQueryNode} child using
* {@link QueryTreeBuilder#QUERY_TREE_BUILDER_TAGID} and applies the boost value
* defined in the {@link BoostQueryNode}.
*/
public class BoostQueryNodeBuilder implements KeywordQueryBuilder {
public BoostQueryNodeBuilder() {
// empty constructor
}
public Query build(final QueryNode queryNode) throws QueryNodeException {
final BoostQueryNode boostNode = (BoostQueryNode) queryNode;
final QueryNode child = boostNode.getChild();
if (child == null) {
return null;
}
final Query query = (Query) child
.getTag(QueryTreeBuilder.QUERY_TREE_BUILDER_TAGID);
query.setBoost(boostNode.getValue());
return query;
}
}