Java Utililty Methods Random Int

int generateRandomInt(final int max)
generate Random Int

return (int) (Math.random() * max);

int generateRandomInt(int min, int max)
generate Random Int

Random random = new Random();
return random.nextInt(max) + min;

int generateRandomInteger(int aStart, int aEnd, Random aRandom)
Erzeugt eine Zufallszahl

if (aStart > aEnd) {
 throw new IllegalArgumentException("Start cannot exceed End.");
long range = (long) aEnd - (long) aStart + 1;
long fraction = (long) (range * aRandom.nextDouble());
int randomNumber = (int) (fraction + aStart);
return randomNumber;

int generateRandomInteger(int start, int end)
Generates a random integer in the interval [start, end] (interval includes both start and end) and returns it.

int range = end - start;
if (_randomNumberGenerator == null)
 _randomNumberGenerator = new Random();
if (range > 0)
 return _randomNumberGenerator.nextInt(range) + start;
return start;

Integer[] generateRandomIntegerArray(int size, int min, int max)
generate Random Integer Array

Random random = new Random(System.currentTimeMillis());
Integer array[] = new Integer[size];
for (int i = 0; i < size; i++) {
 array[i] = random.nextInt(max - min + 1) + min;
return array;

Set generateRandomIntegers(int numbersNeeded, int bound)
generate Random Integers

if (numbersNeeded > bound) {
 throw new RuntimeException("Can not generate number more than bound");
Random rng = new Random();
Set<Integer> generated = new LinkedHashSet<Integer>();
while (generated.size() < numbersNeeded) {
 Integer next = rng.nextInt(bound);
 generated.add(next);
...

int generateRandomIntInRange(int min, int max)
generate Random Int In Range

return min + (int) (Math.random() * ((max - min) + 1));

Integer[] generateRandomIntObj(int range, int noOfElements)
generate Random Int Obj

int arr[] = generateRandomInts(range, noOfElements);
Integer generatedInts[] = new Integer[arr.length];
for (int i = 0; i < arr.length; i++) {
 generatedInts[i] = arr[i];
return generatedInts;

int[] generateRandomInts(int range, int noOfElements)
generate Random Ints

Random randomGenerator = new Random();
int generatedInts[] = new int[noOfElements];
for (int i = 0; i < generatedInts.length; i++) {
 generatedInts[i] = randomGenerator.nextInt(range);
return generatedInts;

int generateRandomIntUpto(int max)
generate Random Int Upto

return nextInt(max);