Lucene example source code file (SegmentTermVector.java)

This example Lucene source code file (SegmentTermVector.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

override, segmenttermvector, segmenttermvector, string, string, stringbuilder, stringbuilder, termfreqvector, termfreqvector, util

The Lucene SegmentTermVector.java source code

package org.apache.lucene.index;

/**
 * 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.*;


class SegmentTermVector implements TermFreqVector {
  private String field;
  private String terms[];
  private int termFreqs[];
  
  SegmentTermVector(String field, String terms[], int termFreqs[]) {
    this.field = field;
    this.terms = terms;
    this.termFreqs = termFreqs;
  }

  /**
   * 
   * @return The number of the field this vector is associated with
   */
  public String getField() {
    return field;
  }

  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append('{');
    sb.append(field).append(": ");
    if(terms != null){
      for (int i=0; i<terms.length; i++) {
        if (i>0) sb.append(", ");
        sb.append(terms[i]).append('/').append(termFreqs[i]);
      }
    }
    sb.append('}');
    
    return sb.toString();
  }

  public int size() {
    return terms == null ? 0 : terms.length;
  }

  public String [] getTerms() {
    return terms;
  }

  public int[] getTermFrequencies() {
    return termFreqs;
  }

  public int indexOf(String termText) {
    if(terms == null)
      return -1;
    int res = Arrays.binarySearch(terms, termText);
    return res >= 0 ? res : -1;
  }

  public int[] indexesOf(String [] termNumbers, int start, int len) {
    // TODO: there must be a more efficient way of doing this.
    //       At least, we could advance the lower bound of the terms array
    //       as we find valid indexes. Also, it might be possible to leverage
    //       this even more by starting in the middle of the termNumbers array
    //       and thus dividing the terms array maybe in half with each found index.
    int res[] = new int[len];

    for (int i=0; i < len; i++) {
      res[i] = indexOf(termNumbers[start+ i]);
    }
    return res;
  }
}