String a = "[1,2]"转换成int数组咋办

我想要的是int a = [1,2],而不是int a =[[1,2]]

String str = "[1,2]";
        String newStr = str.replaceAll("(\\[)|(])", "");
        String[] split = newStr.split(",");
        int[] ans = new int[split.length];
        for (int i = 0; i < split.length; i++) {
            ans[i] = Integer.parseInt(split[i]);
        }
        System.out.println(Arrays.toString(ans));