/*
* Licensed to ElasticSearch and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. ElasticSearch 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.elasticsearch.index.query;
import org.apache.lucene.search.BoostingQuery;
import org.apache.lucene.search.Query;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.xcontent.XContentParser;
import java.io.IOException;
/**
*
*/
public class BoostingQueryParser implements QueryParser {
public static final String NAME = "boosting";
@Inject
public BoostingQueryParser() {
}
@Override
public String[] names() {
return new String[]{NAME};
}
@Override
public Query parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
XContentParser parser = parseContext.parser();
Query positiveQuery = null;
boolean positiveQueryFound = false;
Query negativeQuery = null;
boolean negativeQueryFound = false;
float boost = -1;
float negativeBoost = -1;
String currentFieldName = null;
XContentParser.Token token;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
if ("positive".equals(currentFieldName)) {
positiveQuery = parseContext.parseInnerQuery();
positiveQueryFound = true;
} else if ("negative".equals(currentFieldName)) {
negativeQuery = parseContext.parseInnerQuery();
negativeQueryFound = true;
} else {
throw new QueryParsingException(parseContext.index(), "[boosting] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if ("negative_boost".equals(currentFieldName) || "negativeBoost".equals(currentFieldName)) {
negativeBoost = parser.floatValue();
} else if ("boost".equals(currentFieldName)) {
boost = parser.floatValue();
} else {
throw new QueryParsingException(parseContext.index(), "[boosting] query does not support [" + currentFieldName + "]");
}
}
}
if (positiveQuery == null && !positiveQueryFound) {
throw new QueryParsingException(parseContext.index(), "[boosting] query requires 'positive' query to be set'");
}
if (negativeQuery == null && !negativeQueryFound) {
throw new QueryParsingException(parseContext.index(), "[boosting] query requires 'negative' query to be set'");
}
if (negativeBoost == -1) {
throw new QueryParsingException(parseContext.index(), "[boosting] query requires 'negative_boost' to be set'");
}
// parsers returned null
if (positiveQuery == null || negativeQuery == null) {
return null;
}
BoostingQuery boostingQuery = new BoostingQuery(positiveQuery, negativeQuery, negativeBoost);
if (boost != -1) {
boostingQuery.setBoost(boost);
}
return boostingQuery;
}
}