Duplicates in Array in Java [duplicate]

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• Creating random numbers with no duplicates 15 answers

Random r = new Random();
int a[] = new int[16];

for (int i = 0; i < a.length; i++ ) {
  for( int j = 0; j < a.length; j++) {
    a[j] = (int)(Math.random()* 16);
  }
}

System.out.println(Arrays.toString(a));

This code takes an array with the size 16 and fill it with random numbers. When I print the array, I get duplicates of the same number. I don't want to have duplicates. I would like to remove them and have them replace with another number not used. Can anyone help?