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Lucene example source code file (BasicQueryFactory.java)

This example Lucene source code file (BasicQueryFactory.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

basicqueryfactory, basicqueryfactory, spantermquery, spantermquery, termquery, termquery, toomanybasicqueries, toomanybasicqueries

The Lucene BasicQueryFactory.java source code

package org.apache.lucene.queryParser.surround.query;
/**
 * 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.
 */

/* Create basic queries to be used during rewrite.
 * The basic queries are TermQuery and SpanTermQuery.
 * An exception can be thrown when too many of these are used.
 * SpanTermQuery and TermQuery use IndexReader.termEnum(Term), which causes the buffer usage.
 *
 * Use this class to limit the buffer usage for reading terms from an index.
 * Default is 1024, the same as the max. number of subqueries for a BooleanQuery.
 */
 
import org.apache.lucene.index.Term;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.spans.SpanTermQuery;

public class BasicQueryFactory {
  public BasicQueryFactory(int maxBasicQueries) {
    this.maxBasicQueries = maxBasicQueries;
    this.queriesMade = 0;
  }
  
  public BasicQueryFactory() {
    this(1024);
  }
  
  private int maxBasicQueries;
  private int queriesMade;
  
  public int getNrQueriesMade() {return queriesMade;}
  public int getMaxBasicQueries() {return maxBasicQueries;}
  
  private synchronized void checkMax() throws TooManyBasicQueries {
    if (queriesMade >= maxBasicQueries)
      throw new TooManyBasicQueries(getMaxBasicQueries());
    queriesMade++;
  }
  
  public TermQuery newTermQuery(Term term) throws TooManyBasicQueries {
    checkMax();
    return new TermQuery(term);
  }
  
  public SpanTermQuery newSpanTermQuery(Term term) throws TooManyBasicQueries {
    checkMax();
    return new SpanTermQuery(term);
  }
}


Other Lucene examples (source code examples)

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