Lucene example source code file (SimpleQQParser.java)

This example Lucene source code file (SimpleQQParser.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lucene tags/keywords

booleanquery, booleanquery, parseexception, qualityqueryparser, query, queryparser, simpleqqparser, simpleqqparser, string, string, threadlocal, threadlocal

The Lucene SimpleQQParser.java source code

/**
 * 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.benchmark.quality.utils;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.benchmark.quality.QualityQuery;
import org.apache.lucene.benchmark.quality.QualityQueryParser;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.util.Version;

/**
 * Simplistic quality query parser. A Lucene query is created by passing 
 * the value of the specified QualityQuery name-value pair(s) into 
 * a Lucene's QueryParser using StandardAnalyzer. */
public class SimpleQQParser implements QualityQueryParser {

  private String qqNames[];
  private String indexField;
  ThreadLocal<QueryParser> queryParser = new ThreadLocal();

  /**
   * Constructor of a simple qq parser.
   * @param qqNames name-value pairs of quality query to use for creating the query
   * @param indexField corresponding index field  
   */
  public SimpleQQParser(String qqNames[], String indexField) {
    this.qqNames = qqNames;
    this.indexField = indexField;
  }

  /**
   * Constructor of a simple qq parser.
   * @param qqName name-value pair of quality query to use for creating the query
   * @param indexField corresponding index field  
   */
  public SimpleQQParser(String qqName, String indexField) {
    this(new String[] { qqName }, indexField);
  }

  /* (non-Javadoc)
   * @see org.apache.lucene.benchmark.quality.QualityQueryParser#parse(org.apache.lucene.benchmark.quality.QualityQuery)
   */
  public Query parse(QualityQuery qq) throws ParseException {
    QueryParser qp = queryParser.get();
    if (qp==null) {
      qp = new QueryParser(Version.LUCENE_CURRENT, indexField, new StandardAnalyzer(Version.LUCENE_CURRENT));
      queryParser.set(qp);
    }
    BooleanQuery bq = new BooleanQuery();
    for (int i = 0; i < qqNames.length; i++)
      bq.add(qp.parse(QueryParser.escape(qq.getValue(qqNames[i]))), BooleanClause.Occur.SHOULD);
    
    return bq;
  }

}