.shuffle()

The Collections.shuffle() method randomizes the order of elements in a List.

Syntax

import java.util.*;

Collections.shuffle(myList);

myList will have the order of its elements randomized.

Example

The following example creates an ArrayList then uses Collections.shuffle() to reorder the elements:

import java.util.*;
public class Main {
public static void main(String[] args) {
ArrayList<String> food = new ArrayList<String>();
food.add("Cabbage");
food.add("Pizza");
food.add("Sausage");
food.add("Potatoes");
food.add("Salad");
System.out.println(food);
Collections.shuffle(food);
System.out.println(food);
Collections.shuffle(food);
System.out.println(food);
}
}

This will output something similar to the following:

[Cabbage, Pizza, Sausage, Potatoes, Salad]
[Sausage, Salad, Cabbage, Pizza, Potatoes]
[Potatoes, Pizza, Salad, Sausage, Cabbage]

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