Java Collection - 如何shuffle数组元素

import java.util.Arrays;
import java.util.Random;

public class Main {
  public static void main(String args[]) {
    int[] solutionArray = { 1, 2, 3, 4, 5, 6};
    shuffleArray(solutionArray);
    System.out.println(Arrays.toString(solutionArray));
  }

  static void shuffleArray(int[] ar) {
    Random rnd = new Random();
    for (int i = ar.length - 1; i > 0; i--) {
      int index = rnd.nextInt(i + 1);
      // Simple swap
      int a = ar[index];
      ar[index] = ar[i];
      ar[i] = a;
    }
  }
}