Java Collection How to - Randomize and Shuffle Array of numbers or strings

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Question

We would like to know how to randomize and Shuffle Array of numbers or strings.

Answer

import java.util.Arrays;
import java.util.Random;
/*  w w  w .  j  a v  a  2  s . c  o  m*/
public class Main {

    public static void main(String[] args) 
    {
        int[] nums = new int[100];

        for(int i = 0; i < nums.length; ++i) 
        {
            nums[i] = i + 1;
        }

        Random generator = new Random();
        for(int i = 0; i < nums.length; ++i) 
        {           
            int arrayIndex = generator.nextInt(nums.length - i);         
            int tmp = nums[nums.length - 1 - i];
            nums[nums.length - 1 - i] = nums[arrayIndex];
            nums[arrayIndex] = tmp;
        }
        System.out.println(Arrays.toString(nums));
    }

}

The code above generates the following result.

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