/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search 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.index.Term;
import org.apache.lucene.search.FuzzyQuery;
import org.apache.lucene.search.Query;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.mapper.MapperService;
import java.io.IOException;
import static org.elasticsearch.index.query.support.QueryParsers.*;
/**
* @author kimchy (shay.banon)
*/
public class FuzzyQueryParser implements QueryParser {
public static final String NAME = "fuzzy";
@Inject public FuzzyQueryParser() {
}
@Override public String[] names() {
return new String[]{NAME};
}
@Override public Query parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
XContentParser parser = parseContext.parser();
XContentParser.Token token = parser.nextToken();
assert token == XContentParser.Token.FIELD_NAME;
String fieldName = parser.currentName();
String value = null;
float boost = 1.0f;
String minSimilarity = "0.5";
int prefixLength = FuzzyQuery.defaultPrefixLength;
int maxExpansions = FuzzyQuery.defaultMaxExpansions;
token = parser.nextToken();
if (token == XContentParser.Token.START_OBJECT) {
String currentFieldName = null;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else {
if ("term".equals(currentFieldName)) {
value = parser.text();
} else if ("value".equals(currentFieldName)) {
value = parser.text();
} else if ("boost".equals(currentFieldName)) {
boost = parser.floatValue();
} else if ("min_similarity".equals(currentFieldName) || "minSimilarity".equals(currentFieldName)) {
minSimilarity = parser.text();
} else if ("prefix_length".equals(currentFieldName) || "prefixLength".equals(currentFieldName)) {
prefixLength = parser.intValue();
} else if ("max_expansions".equals(currentFieldName) || "maxExpansions".equals(currentFieldName)) {
maxExpansions = parser.intValue();
}
}
}
parser.nextToken();
} else {
value = parser.text();
// move to the next token
parser.nextToken();
}
if (value == null) {
throw new QueryParsingException(parseContext.index(), "No value specified for fuzzy query");
}
Query query = null;
MapperService.SmartNameFieldMappers smartNameFieldMappers = parseContext.smartFieldMappers(fieldName);
if (smartNameFieldMappers != null) {
if (smartNameFieldMappers.hasMapper()) {
query = smartNameFieldMappers.mapper().fuzzyQuery(value, minSimilarity, prefixLength, maxExpansions);
}
}
if (query == null) {
query = new FuzzyQuery(new Term(fieldName, value), Float.parseFloat(minSimilarity), prefixLength, maxExpansions);
}
query.setBoost(boost);
return wrapSmartNameQuery(query, smartNameFieldMappers, parseContext);
}
}