public static String durationFormat(Integer totalSeconds) {

        if (totalSeconds == null || totalSeconds < 1) {

            return "00:01";

        }

        //将秒格式化成HH:mm:ss

        //这里应该用Duration更合理，但它不能格式化成字符串

        //而使用LocalTime，在时间超过24小时后格式化也会有问题（！）

        int hours = totalSeconds / 3600;

        int rem = totalSeconds % 3600;

        int minutes = rem / 60;

        int seconds = rem % 60;

        if (hours <= 0) {

            return String.format("%02d:%02d", minutes, seconds);

        }

        return String.format("%02d:%02d:%02d", hours, minutes, seconds);

    }