Shuffle an array

https://leetcode.com/problems/shuffle-an-array

Shuffle a set of numbers without duplicates.

Example:

// Init an array with set 1, 2, and 3.
int[] nums = {1,2,3};
Solution solution = new Solution(nums);

// Shuffle the array [1,2,3] and return its result. Any permutation of [1,2,3] must equally likely to be returned.
solution.shuffle();

// Resets the array back to its original configuration [1,2,3].
solution.reset();

// Returns the random shuffling of array [1,2,3].
solution.shuffle();

Implementation :

class Solution {
    private int[] array;
    private int[] cloned;
    private Random rand = new Random();
    
    public Solution(int[] nums) {
        array = nums;
        cloned = nums.clone();
    }
    
    private List<Integer> getArrayCopy() {
        List<Integer> asList = new ArrayList<Integer>();
        for (int i = 0; i < array.length; i++) {
            asList.add(array[i]);
        }
        return asList;
    }
    
    /** Resets the array to its original configuration and return it. */
    public int[] reset() {
        return cloned;
    }
    
    /** Returns a random shuffling of the array. */
    public int[] shuffle() {
        List<Integer> aux = getArrayCopy();
        for (int i = 0; i < array.length; i++) {
            int removeIdx = rand.nextInt(aux.size());
            array[i] = aux.get(removeIdx);
            aux.remove(removeIdx);
        }

        return array;
    }
}

/**
 * Your Solution object will be instantiated and called as such:
 * Solution obj = new Solution(nums);
 * int[] param_1 = obj.reset();
 * int[] param_2 = obj.shuffle();
 */