java中快速排序有时成功有时失败

public class Sorting {

public static void main(String[] args) {
// TODO Auto-generated method stub
int len = 10;
int arr[] = new int [len];
for(int i=0;i<len;i++)
{
//Math.random()表示0~1之间的随机数
arr[i] = (int)(Math.random()*10000);
}
Quick_Sort qs = new Quick_Sort();
qs.sort(arr);

for(int i=0;i<arr.length;i++)
{
System.out.print(arr[i]+" ");
}
}

}
class Quick_Sort
{
public void sort(int arr[])
{
int f = 0;
int l = (arr.length-1);
this.digui(f, l, arr);

}
private void digui(int first,int last,int arr[])
{
int temp = arr[first];
int f = first;
int l = last;
while(f<l)
{
while(f<l&&temp<=arr[l])
{
l--;
}
arr[f] = arr[l];

while(f=arr[f])
{
f++;
}
arr[l] = arr[f];

}
arr[f] = temp;

if(first<last)
{
this.digui(first, f-1, arr);

this.digui(f+1,last, arr);
}

}
}

为什么运行有时成功有时抛出异常

程序运行了下，会数组越界，仔细检查下你的程序，没有本地调试器，没办法帮你调试

参考：http://blog.csdn.net/wangkuifeng0118/article/details/7286332
自己修改下

你再运行几次它又可以成功

 public static void quickSort(int[] arr,int low,int high){
        if(high > low){
            int part = partition(arr,low,high);
            //System.out.println("part="+part);
            quickSort(arr,low,part - 1);
            quickSort(arr,part+1,high);
        }
    }
    //找寻分界点
    public static int partition(int[] arr,int low , int high){
        int first = low;
        int pivot = arr[low];
        low++;
        while(high > low){
            //从左边找比pivot大的数
            while(low <= high && arr[low] <= pivot ){
                low++;
            }
            //从右边找比pivot小或等于的数
            while(high >= low && arr[high] > pivot ){
                high--;
            }
            //交换
            if(high > low){
                int temp = arr[high];
                arr[high] = arr[low];
                arr[low] = temp;
            }
        }
        //此时high = low - 1;
        //且high之前的元素都小于等于pivot,low之后的元素都大于pivot
        //System.out.println("low="+low+";high="+high+"："+Arrays.toString(arr));
        if(high > first){
            int temp = arr[high];
            arr[high] = arr[first];
            arr[first] = temp;
            //System.out.println("part="+high+"："+Arrays.toString(arr));
            return high;
        }else{
            //System.out.println("part="+high+"："+Arrays.toString(arr));
            return first;
        }
    }

 public static void main(String[] args) {
         // TODO Auto-generated method stub
         int len = 10;
         int arr[] = new int [len];
         for(int i=0;i<len;i++)
         {
         //Math.random()表示0~1之间的随机数
        arr[i] = (int)(Math.random()*10000);
        System.out.println(arr[i]);
         }
         Quick_Sort qs = new Quick_Sort();
         qs.sort(arr);

        for(int i=0;i<arr.length;i++)
         {
         System.out.print(arr[i]+" ");
         }
         }

        }
         class Quick_Sort
         {
         public void sort(int arr[])
         {
         int f = 0;
         int l = (arr.length-1);
         this.digui(f, l, arr);

        }
         private void digui(int first,int last,int arr[])
         {
         int temp = arr[first];
         int f = first;
         int l = last;
         while(f<l)
         {
             while(f<l&&temp<=arr[l])
             {
                 l--;
             }
//           if(f<l){
//               arr[f]=arr[l];
//               f++;
//           }
            while(f<l && arr[f]<=temp )
             {
                f++;
             }
            if(f!=first && f!=l){
                int a=arr[f];
                arr[f] = arr[l];
                arr[l] = a;
            }
        }
        arr[first]=arr[f];
        arr[f]=temp;

        if(first<last)
         {
            this.digui(first+1, last, arr);
            this.digui(first,last-1, arr);
         }

        }

失败时的错误信息是什么呢