Shuffle elements of ArrayList with Java Collections

In order to shuffle elements of ArrayList with Java Collections, we use the Collections.shuffle() method. The java.util.Collections.shuffle() method randomly permutes the list using a default source of randomness.

Declaration −The java.util.Collections.shuffle() method is declared as follows −

public static void shuffle(List <?> list)

Let us see a program to shuffle elements of ArrayList with Java Collections −

Example

 Live Demo

import java.util.*;
public class Example {
   public static void main (String[] args) {
      ArrayList<Integer> list = new ArrayList<Integer>();
      list.add(1);
      list.add(2);
      list.add(7);
      list.add(8);
      list.add(3);
      list.add(9);
      System.out.println("Original list : " + list);
      Collections.shuffle(list); // shuffling the list
      System.out.println("Shuffled list : " + list);
   }
}

Output

Original list : [1, 2, 7, 8, 3, 9]
Shuffled list : [3, 8, 7, 9, 1, 2]