lucene/queryparser/src/java/org/apache/lucene/queryparser/flexible/standard/processors/RegexpQueryNodeProcessor.java

/*
 * 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.
 */
package org.apache.lucene.queryparser.flexible.standard.processors;

import java.util.List;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.queryparser.flexible.core.QueryNodeException;
import org.apache.lucene.queryparser.flexible.core.nodes.QueryNode;
import org.apache.lucene.queryparser.flexible.core.processors.QueryNodeProcessorImpl;
import org.apache.lucene.queryparser.flexible.standard.config.StandardQueryConfigHandler.ConfigurationKeys;
import org.apache.lucene.queryparser.flexible.standard.nodes.RegexpQueryNode;

/** Processor for Regexp queries. */
public class RegexpQueryNodeProcessor extends QueryNodeProcessorImpl {

  @Override
  protected QueryNode preProcessNode(QueryNode node) throws QueryNodeException {
    return node;
  }

  @Override
  protected QueryNode postProcessNode(QueryNode node) throws QueryNodeException {
    if (node instanceof RegexpQueryNode) {
      RegexpQueryNode regexpNode = (RegexpQueryNode) node;
      Analyzer analyzer = getQueryConfigHandler().get(ConfigurationKeys.ANALYZER);
      if (analyzer != null) {
        String text = regexpNode.getText().toString();
        // because we call utf8ToString, this will only work with the default TermToBytesRefAttribute
        text = analyzer.normalize(regexpNode.getFieldAsString(), text).utf8ToString();
        regexpNode.setText(text);
      }
    }
    return node;
  }

  @Override
  protected List<QueryNode> setChildrenOrder(List<QueryNode> children) throws QueryNodeException {
    return children;
  }

}