I'm developing multiple choice question game. It has four integer choices. Options are stored in an array list. I want to display the choices with the elements in the array in random order with no repetition each time. Please give me the solution. 

```
int ans[] = new int[] { sum, sum + 1, sum + 2, sum - 1 };

    ArrayList<Integer> number = new ArrayList<Integer>();
    for (int i : number) {
        number.add(ans[i]);
    }

    Collections.shuffle(number);

    but1.setText("" + number.get(0));
    but2.setText("" + number.get(1));
    but3.setText("" + number.get(2));
    but4.setText("" + number.get(3));

```