bubblesorter.java

著名的uncle Bob的Agile software development的代码

public class BubbleSorter
{
  static int operations = 0;
  public static int sort(int [] array)
  {
    operations = 0;
    if (array.length <= 1)
      return operations;

    for (int nextToLast = array.length-2; nextToLast >= 0; nextToLast--)
      for (int index = 0; index <= nextToLast; index++)
        compareAndSwap(array, index);

    return operations;
  }

  private static void swap(int[] array, int index)
  {
    int temp = array[index];
    array[index] = array[index+1];
    array[index+1] = temp;
  }

  private static void compareAndSwap(int[] array, int index)
  {
    if (array[index] > array[index+1])
      swap(array, index);
    operations++;
  }
}