1. Random r = new Random()
    2. Copy an array in Java with Arrays.copyOf(array, array.length)
        Integer[] otherArr = Arrays.copyOf(arr, arr.length);

    // Other: file:///Users/aaa/myfile/bitbucket/java/Shuffle.java    
    // From Aron.java
    public static Integer[] shuffle(Integer[] arr){
        Integer len = arr.length;
        Integer[] array = Arrays.copyOf(arr, len);
        Random r = new Random();
        Integer inxLen = len - 1;
        for(int i = 0; i < len - i; i++){
            Integer inx = r.nextInt(len - i);
            Integer tmp = array[inx];
            array[inx] = array[inxLen - i];
            array[inxLen - i] = tmp;
        }
        return array;
    }