package org.apache.lucene.queryParser.standard.processors;
/**
* 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.util.List;
import org.apache.lucene.queryParser.core.QueryNodeException;
import org.apache.lucene.queryParser.core.config.FieldConfig;
import org.apache.lucene.queryParser.core.config.QueryConfigHandler;
import org.apache.lucene.queryParser.core.nodes.BoostQueryNode;
import org.apache.lucene.queryParser.core.nodes.FieldableNode;
import org.apache.lucene.queryParser.core.nodes.QueryNode;
import org.apache.lucene.queryParser.core.processors.QueryNodeProcessorImpl;
import org.apache.lucene.queryParser.standard.config.BoostAttribute;
/**
* This processor iterates the query node tree looking for every
* {@link FieldableNode} that has the attribute {@link BoostAttribute} in its
* config. If there is, the boost is applied to that {@link FieldableNode}. <br/>
*
* @see BoostAttribute
* @see QueryConfigHandler
* @see FieldableNode
*/
public class BoostQueryNodeProcessor extends QueryNodeProcessorImpl {
@Override
protected QueryNode postProcessNode(QueryNode node) throws QueryNodeException {
if (node instanceof FieldableNode &&
(node.getParent() == null || !(node.getParent() instanceof FieldableNode))) {
FieldableNode fieldNode = (FieldableNode) node;
QueryConfigHandler config = getQueryConfigHandler();
if (config != null) {
FieldConfig fieldConfig = config.getFieldConfig(fieldNode.getField());
if (fieldConfig != null && fieldConfig.hasAttribute(BoostAttribute.class)) {
BoostAttribute boostAttr = fieldConfig.getAttribute(BoostAttribute.class);
return new BoostQueryNode(node, boostAttr.getBoost());
}
}
}
return node;
}
@Override
protected QueryNode preProcessNode(QueryNode node) throws QueryNodeException {
return node;
}
@Override
protected List<QueryNode> setChildrenOrder(List<QueryNode> children)
throws QueryNodeException {
return children;
}
}