Java Utililty Methods Array Shuffle

List of utility methods to do Array Shuffle

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Description

The list of methods to do Array Shuffle are organized into topic(s).

Method

Listshuffled(List list, Random random)
shuffled 
Collections.shuffle(list, random);
return list;
ListshuffledList(List list)

shuffledList

ArrayList<T> result = new ArrayList<T>(list);
Collections.shuffle(result);
return result;
voidshuffleInPlace(E[] elems, Random rand)
shuffle In Place 
for (int j = elems.length - 1; j > 0; j--) {
    int randIndex = rand.nextInt(j + 1);
    E tmp = elems[randIndex];
    elems[randIndex] = elems[j];
    elems[j] = tmp;
voidshuffleInPlace(int[] toShuffle, Random random)
Randomly shuffle the specified integer array using a Fisher-Yates shuffle algorithm 
for (int i = 0; i < toShuffle.length - 1; i++) {
    int j = i + random.nextInt(toShuffle.length - i);
    int temp = toShuffle[i];
    toShuffle[i] = toShuffle[j];
    toShuffle[j] = temp;
voidshuffleIntArray(int[] arr)
shuffle Int Array 
if (arr == null || arr.length == 0)
    throw new IllegalArgumentException("Array cannot be null or have zero length");
for (int i = arr.length - 1; i > 0; i--) {
    int index = rnd.nextInt(i + 1);
    int a = arr[index];
    arr[index] = arr[i];
    arr[i] = a;
int[]shuffleIntArray(int[] array)
shuffle Int Array 
int[] copy = array.clone();
Random rnd = new Random();
for (int i = copy.length - 1; i > 0; i--) {
    int index = rnd.nextInt(i + 1);
    int a = copy[index];
    copy[index] = copy[i];
    copy[i] = a;
return copy;
voidshuffleList(List list)
Shuffles a list. 
long seed = System.nanoTime();
Collections.shuffle(list, new Random(seed));
voidshuffleList(List list)
Shuffles the input list using an implementation of the Knuth "Algorithm P" shuffle. 
Random randomGenerator = new Random();
for (int loopIndex = list.size() - 1; loopIndex > 0; loopIndex--) {
    int randomIndex = randomGenerator.nextInt(loopIndex + 1);
    Collections.swap(list, randomIndex, loopIndex);
voidshuffleSublist(List objects, int start, int end)
Shuffle the elements between the specified start and end index both inclusive. 
for (int index = start; index <= end; index++) {
    T current = objects.get(index);
    int randomIndex = nextInt(start, end);
    T randomObject = objects.get(randomIndex);
    objects.set(index, randomObject);
    objects.set(randomIndex, current);