写一个快速排序java代码

public class QuickSort {
public static void sort(int[] arr, int low, int high) {
if (arr == null || arr.length == 0)
return;

if (low >= high)
return;

// 取第一个数为基准
int middle = low + (high - low) / 2;
int pivot = arr[middle];

// 将比基准小的放左边，比基准大的放右边
int i = low, j = high;
while (i <= j) {
while (arr[i] < pivot)
i++;

while (arr[j] > pivot)
j--;

if (i <= j) {
int temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
i++;
j--;
}
}

// 递归调用
if (low < j)
sort(arr, low, j);

if (high > i)
sort(arr, i, high);
}
}