数组翻转的一道题目

老赵博客里面的一道题目,以下是个人答案:

 1 /**
 2      * Besides this,stack could be used to solved it.
 3      * @param array
 4      * @param begin
 5      * @param end
 6      * @throws Exception
 7      */
 8     public static void Reverse(int[] array,int begin,int end) throws Exception{
 9         
10         if(array==null)
11             throw new NullPointerException("Array is null"); //not new Exception
12         if(array.length==0)
13             throw new ArrayIndexOutOfBoundsException("Array is empty"); //not new Exception
14         if(begin<0)
15             throw new ArrayIndexOutOfBoundsException("begin is less than 0"); //not new Exception
16         if(end<begin)
17             throw new ArrayIndexOutOfBoundsException("end is less than begin"); //not new Exception
18         //Missing this
19         if(end>array.length)
20             throw new Exception("end is larger than the length of array");
21         
22         //
23         while(end>begin){
24             int temp = array[begin];
25             array[begin]=array[end];
26             array[end]=temp;
27             
28             end--;
29             begin++;
30         }
31     }
  • 解法有很多,利用stack也可以,但交换的方法比较优雅
  • 参数的检验一定要到位。而且不要打印错误,要抛出异常。抛出的异常尽量精准,不要全抛出Exception
  • 进一步会考使用单元测试,提供测试用例
posted @ 2013-03-12 23:22  macemers  阅读(286)  评论(0编辑  收藏  举报