日期时间转换

	long days = mss / (1000 * 60 * 60 * 24);

    long hours = (mss % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60);

    long minutes = (mss % (1000 * 60 * 60)) / (1000 * 60);

    long seconds = (mss % (1000 * 60)) / 1000;

    return days + "天" + hours + "时" + minutes + "分"
            + seconds + "秒 ";