java计算两个日期相差多少天小时分钟等

    public static void main(String[] args) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        long time = sdf.parse("2022-03-21 23:59:59", new ParsePosition(0)).getTime();
        long nd = 1000 * 24 * 60 * 60;
        long nh = 1000 * 60 * 60;
        long nm = 1000 * 60;
        long ns = 1000;
//        // 获得两个时间的毫秒时间差异
        long diff = time - System.currentTimeMillis() + 1000;
//        // 计算差多少天
        long day = diff / nd;
//        // 计算差多少小时
        long hour = diff % nd / nh;
//        // 计算差多少分钟
        long min = diff % nd % nh / nm;
        // 计算差多少秒//输出结果
        long sec = diff % nd % nh % nm / ns;
        System.out.println(day + "天" + hour + "小时" + min + "分钟" + sec + "秒");
    }