方法一：推薦

直接呼叫Collections.shuffle(list)，這個是系統方法，比較簡單實用

String[] arr = new String[] {"1", "2"};
List list = Arrays.asList(arr);

直接呼叫shuffle，就是隨機排序 

Collections.shuffle(list);

方法二：

演算法：順序遍歷，每次生成一個隨機位置，和當前位置的元素互換。

    public static ArrayList randomList(ArrayList sourceList) {
        if (sourceList == null || sourceList.size() == 0) {
            return sourceList;
        }
        ArrayList randomList = new ArrayList(sourceList.size());
        do {
            int randomIndex = Math.abs(new Random().nextInt(sourceList.size()));
            randomList.add(sourceList.remove(randomIndex));
        } while (sourceList.size() > 0);
        return randomList;
    }
 

附帶陣列操作方法

    /**
     * 對給定數目的自0開始步長為1的數字序列進行亂序
     *
     * @param no 給定數目
     * @return 亂序後的陣列
     */
    public static int[] getSequence(int no) {
        int[] sequence = new int[no];
        for (int i = 0; i < no; i++) {
            sequence[i] = i;
        }
        Random random = new Random();
        for (int i = 0; i < no; i++) {
            int p = random.nextInt(no);
            int tmp = sequence[i];
            sequence[i] = sequence[p];
            sequence[p] = tmp;
        }
        random = null;
        return sequence;
    }