JAVAランダムに配列の順序を乱す

import java.util.Random;  
  
public class RandomSort {  
    private Random random = new Random();  
    //      
    private static final int SIZE = 10;  
    //         
    private int[] positions = new int[SIZE];  
      
    public RandomSort() {  
        for(int index=0; index=0; index--) {  
            // 0 index         ， index        
            exchange(random.nextInt(index+1), index);  
        }  
        printPositions();  
    }  
      
    //      
    private void exchange(int p1, int p2) {  
        int temp = positions[p1];  
        positions[p1] = positions[p2];  
        positions[p2] = temp;  //    
    }  
      
    //        
    private void printPositions() {  
        for(int index=0; index