CounterGenerator.java

/**
 * Copyright (c) 2010 Yahoo! Inc. All rights reserved.
 *
 * Licensed 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. See accompanying
 * LICENSE file.
 */
package com.googlecode.concurrentlinkedhashmap.generator;

/**
 * Generates a sequence of integers 0, 1, ...
 *
 * @author Brian Cooper
 * @see <a href="http://research.yahoo.com/Web_Information_Management/YCSB">YCSB</a>
 */
public class CounterGenerator extends IntegerGenerator {
  int counter;

  /**
   * Create a counter that starts at countstart.
   */
  public CounterGenerator(int countstart) {
    counter = countstart;
    setLastInt(countstart - 1);
  }

  /**
   * If the generator returns numeric (integer) values, return the next value as
   * an int. Default is to return -1, which is appropriate for generators that
   * do not return numeric values.
   */
  @Override
  public synchronized int nextInt() {
    int lastint = counter;
    counter++;
    setLastInt(lastint);
    return lastint;
  }
}