/**

*@author Linyco

*利用選擇排序法對(duì)數(shù)組排序，數(shù)組中元素必須實(shí)現(xiàn)了Comparable接口。

*/

public class ChooseSort implements SortStrategy

{

       /**

       *對(duì)數(shù)組obj中的元素以選擇排序算法進(jìn)行排序

       */

       public void sort(Comparable[] obj)

       {

              if (obj == null)

              {

                     throw new NullPointerException("The argument can not be null!");

              }

              Comparable tmp = null;

              int index = 0;

              for (int i = 0 ;i < obj.length - 1 ;i++ )

              {

                     index = i;

                     tmp = obj[i];

                     for (int j = i + 1 ;j < obj.length ;j++ )

                     {

                            //對(duì)鄰接的元素進(jìn)行比較，如果后面的小，就記下它的位置

                            if (tmp.compareTo(obj[j]) > 0)

                            {

                                   tmp = obj[j];   //要每次比較都記錄下當(dāng)前小的這個(gè)值!

                                   index = j;

                            }

                     }

                     //將最小的元素交換到前面

                     tmp = obj[i];

                     obj[i] = obj[index];

                     obj[index] = tmp;

              }

       }

}