int[] array;
array = new int[12];
for (int i = 0; i < array.length; i++) {
    array[i] = ((int)(Math.random() * 12) - 15);
    System.out.println(array[i]);
}

int[] array = new int[12];
for (int i = 0; i < array.length; i++) {
    array[i] = (int) Math.round((Math.random() * 30) - 15);
    System.out.println(array[i]);
}

int[] array = new int[12];
for (int i = 0; i < array.length; i++) {
    array[i] = ((int)(Math.random() * 31) - 15);
    System.out.println(array[i]);
}

for(int i = 0; i < 12; i++){
     System.out.println(random.nextInt(31) - 15);
}

private static Random rand = new Random();

public static int getRandom(int lo, int hi) {
   return lo + rand.nextInt(hi - lo + 1);
} // getRandom