Lucene example source code file (WeightedSpanTerm.java)

This example Lucene source code file (WeightedSpanTerm.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

arraylist, arraylist, iterator, list, positionspan, positionspan, string, string, util, weightedspanterm, weightedspanterm, weightedterm

The Lucene WeightedSpanTerm.java source code

package org.apache.lucene.search.highlight;


/**
 * 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.ArrayList;
import java.util.Iterator;
import java.util.List;


/**
 * Lightweight class to hold term, weight, and positions used for scoring this
 * term.
 */
public class WeightedSpanTerm extends WeightedTerm{
  boolean positionSensitive;
  private List<PositionSpan> positionSpans = new ArrayList();

  /**
   * @param weight
   * @param term
   */
  public WeightedSpanTerm(float weight, String term) {
    super(weight, term);
    this.positionSpans = new ArrayList<PositionSpan>();
  }

  /**
   * @param weight
   * @param term
   * @param positionSensitive
   */
  public WeightedSpanTerm(float weight, String term, boolean positionSensitive) {
    super(weight, term);
    this.positionSensitive = positionSensitive;
  }

  /**
   * Checks to see if this term is valid at <code>position.
   *
   * @param position
   *            to check against valid term positions
   * @return true iff this term is a hit at this position
   */
  public boolean checkPosition(int position) {
    // There would probably be a slight speed improvement if PositionSpans
    // where kept in some sort of priority queue - that way this method
    // could
    // bail early without checking each PositionSpan.
    Iterator<PositionSpan> positionSpanIt = positionSpans.iterator();

    while (positionSpanIt.hasNext()) {
      PositionSpan posSpan = positionSpanIt.next();

      if (((position >= posSpan.start) && (position <= posSpan.end))) {
        return true;
      }
    }

    return false;
  }

  public void addPositionSpans(List<PositionSpan> positionSpans) {
    this.positionSpans.addAll(positionSpans);
  }

  public boolean isPositionSensitive() {
    return positionSensitive;
  }

  public void setPositionSensitive(boolean positionSensitive) {
    this.positionSensitive = positionSensitive;
  }

  public List<PositionSpan> getPositionSpans() {
    return positionSpans;
  }
}


// Utility class to store a Span
class PositionSpan {
  int start;
  int end;

  public PositionSpan(int start, int end) {
    this.start = start;
    this.end = end;
  }
}