Lucene example source code file (CharArrayIterator.java)

This example Lucene source code file (CharArrayIterator.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

characteriterator, chararrayiterator, chararrayiterator, done, done, illegal, illegal, illegalargumentexception, object, object, override, position, text

The Lucene CharArrayIterator.java source code

package org.apache.lucene.analysis.icu.segmentation;

/**
 * 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.text.CharacterIterator;

/**
 * Wraps a char[] as CharacterIterator for processing with a BreakIterator
 * @lucene.experimental
 */
final class CharArrayIterator implements CharacterIterator {
  private char array[];
  private int start;
  private int index;
  private int length;
  private int limit;

  public char [] getText() {
    return array;
  }
  
  public int getStart() {
    return start;
  }
  
  public int getLength() {
    return length;
  }
  
  /**
   * Set a new region of text to be examined by this iterator
   * 
   * @param array text buffer to examine
   * @param start offset into buffer
   * @param length maximum length to examine
   */
  void setText(final char array[], int start, int length) {
    this.array = array;
    this.start = start;
    this.index = start;
    this.length = length;
    this.limit = start + length;
  }

  public char current() {
    return (index == limit) ? DONE : array[index];
  }

  public char first() {
    index = start;
    return current();
  }

  public int getBeginIndex() {
    return 0;
  }

  public int getEndIndex() {
    return length;
  }

  public int getIndex() {
    return index - start;
  }

  public char last() {
    index = (limit == start) ? limit : limit - 1;
    return current();
  }

  public char next() {
    if (++index >= limit) {
      index = limit;
      return DONE;
    } else {
      return current();
    }
  }

  public char previous() {
    if (--index < start) {
      index = start;
      return DONE;
    } else {
      return current();
    }
  }

  public char setIndex(int position) {
    if (position < getBeginIndex() || position > getEndIndex())
      throw new IllegalArgumentException("Illegal Position: " + position);
    index = start + position;
    return current();
  }

  @Override
  public Object clone() {
    CharArrayIterator clone = new CharArrayIterator();
    clone.setText(array, start, length);
    clone.index = index;
    return clone;
  }
}