找出特定日期某个时间的天数、小时数和分钟数

Question

我对java开发相当陌生，遇到了一个需要帮助的问题。

我需要找出每天（如果适用的话）的时间和分钟，直到上午8:30。然而，由于这是一个“学校倒计时”，代码必须知道，如果下一个上午8:30是在周六或周日，它应该显示到周一上午8:30的时间。再说一次，如果这没有多大意义，我很抱歉。因此，我处理这个问题的逻辑方法是：

>

Date dt = new Date();
Calendar c = Calendar.getInstance();
c.setTime(dt);
c.set(Calendar.HOUR_OF_DAY, 0);
c.set(Calendar.MINUTE, 0);
c.set(Calendar.SECOND, 0);
c.set(Calendar.MILLISECOND, 0);
dt = c.getTime();
DateFormat dateFormat = new SimpleDateFormat("dd");
String datetommorow = dateFormat.format(dt);
int date22 = Integer.parseInt(datetommorow);
int date33 = date22 + 1;
Integer.toString(date33);

正如你从这次尝试中看到的，我正在努力解决这个问题。任何帮助都将不胜感激，如果您需要更多信息，请随时询问

Answer 1

你可能想看看Joda Time for Android。此外，DateFormat在多线程环境中本质上是不安全的，Date API通常很难看，而且很糟糕（至少对于

Answer 2

这应该对你有帮助

        Calendar cal = Calendar.getInstance();
        cal.add(Calendar.DAY_OF_MONTH, 1);
        SimpleDateFormat sdf = new SimpleDateFormat("EEEE");
        System.out.println("Tommorow is : " + sdf.format(cal.getTime()));

        Calendar future = Calendar.getInstance(); //future time
        future.add(Calendar.DAY_OF_MONTH, 1);
        future.set(Calendar.HOUR_OF_DAY,8); // Set hours to 8'O clock
        future.set(Calendar.MINUTE,30);
        Calendar now = Calendar.getInstance(); //get current time
        long hoursDiff = (future.getTimeInMillis() - now.getTimeInMillis())/(60 * 60 * 1000);
        long minDiff = (future.getTimeInMillis() - now.getTimeInMillis())/(60 * 1000);
        System.out.println("Hours left : " + hoursDiff);
        System.out.println("Minutes left : " + minDiff);

Answer 3

        Calendar now = Calendar.getInstance();
        int currentDay = now.get(Calendar.DAY_OF_WEEK);

        Calendar school = Calendar.getInstance();
        school.add(Calendar.DAY_OF_YEAR, 1);

        if (currentDay == Calendar.SATURDAY)
        {
            school.add(Calendar.DAY_OF_YEAR, 1);
        }
        else if (currentDay == Calendar.FRIDAY)
        {
            school.add(Calendar.DAY_OF_YEAR, 2);
        }

        school.set(Calendar.HOUR_OF_DAY, 8);
        school.set(Calendar.MINUTE, 30);

        long millisLeft = school.getTimeInMillis() - now.getTimeInMillis();
        long hoursLeft = millisLeft / (60 * 60 * 1000);
        long minutesLeft =  (millisLeft % (60 * 60 * 1000)) / (60 * 1000);