java怎么随机打乱数组顺序

import java.util.Random;  
  
public class RandomSort {  
    private Random random = new Random();  
    //数组大小  
    private static final int SIZE = 10;  
    //要重排序的数组  
    private int[] positions = new int[SIZE];  
      
    public RandomSort() {  
        for(int index=0; index<SIZE; index++) {  
            //初始化数组，以下标为元素值  
            positions[index] = index;  
        }  
        //顺序打印出数组的值  
        printPositions();
    }  
      
    //重排序  
    public void changePosition() {  
        for(int index=SIZE-1; index>=0; index--) {  
            //从0到index处之间随机取一个值，跟index处的元素交换  
            exchange(random.nextInt(index+1), index);  
        }  
        printPositions();  
    }  
      
    //交换位置  
    private void exchange(int p1, int p2) {  
        int temp = positions[p1];  
        positions[p1] = positions[p2];  
        positions[p2] = temp;  //更好位置
    }  
      
    //打印数组的值  
    private void printPositions() {  
        for(int index=0; index<SIZE; index++) {  
            System.out.print(positions[index]+" ");           
        }  
        System.out.println();  
    }  
  
    public static void main(String[] args) {  
        RandomSort rs = new RandomSort();  
        rs.changePosition();  
        rs.changePosition();  
        rs.changePosition();  
    }  
}