Lucene example source code file (ScoreOrderFragmentsBuilder.java)

This example Lucene source code file (ScoreOrderFragmentsBuilder.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

basefragmentsbuilder, comparator, list, override, scorecomparator, scorecomparator, scoreorderfragmentsbuilder, scoreorderfragmentsbuilder, string, string, util, weightedfraginfo, weightedfraginfo

The Lucene ScoreOrderFragmentsBuilder.java source code

package org.apache.lucene.search.vectorhighlight;

/**
 * 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.
 */

import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import org.apache.lucene.search.vectorhighlight.FieldFragList.WeightedFragInfo;

/**
 * An implementation of FragmentsBuilder that outputs score-order fragments.
 */
public class ScoreOrderFragmentsBuilder extends BaseFragmentsBuilder {

  /**
   * a constructor.
   */
  public ScoreOrderFragmentsBuilder(){
    super();
  }

  /**
   * a constructor.
   * 
   * @param preTags array of pre-tags for markup terms.
   * @param postTags array of post-tags for markup terms.
   */
  public ScoreOrderFragmentsBuilder( String[] preTags, String[] postTags ){
    super( preTags, postTags );
  }

  /**
   * Sort by score the list of WeightedFragInfo
   */
  @Override
  public List<WeightedFragInfo> getWeightedFragInfoList( List src ) {
    Collections.sort( src, new ScoreComparator() );
    return src;
  }

  public static class ScoreComparator implements Comparator<WeightedFragInfo> {

    public int compare( WeightedFragInfo o1, WeightedFragInfo o2 ) {
      if( o1.totalBoost > o2.totalBoost ) return -1;
      else if( o1.totalBoost < o2.totalBoost ) return 1;
      // if same score then check startOffset
      else{
        if( o1.startOffset < o2.startOffset ) return -1;
        else if( o1.startOffset > o2.startOffset ) return 1;
      }
      return 0;
    }
  }
}