如何将Java Date对象的值设置为昨天？ [重复]

Possible Duplicate:
Get yesterday's date using Date

可能重复：使用日期获取昨天的日期

What is an elegant way set to a Java Date object's value to yesterday?

什么是设置为Java Date对象的值的优雅方式到昨天？

6 个解决方案

#1

Do you mean to go back 24 hours in time.

你的意思是24小时回去。

 Date date = new Date(System.currentTimeMillis() - 24 * 60 * 60 * 1000L);

or to go back one day at the time same time (this can be 23 or 25 hours depending on daylight savings)

或者在同一时间返回一天（这可能是23或25小时，具体取决于夏令时）

 Calendar cal = Calendar.getInstance();
 cal.add(Calendar.DATE, -1);

These are not exactly the same due to daylight saving.

由于夏令时，这些并不完全相同。

#2

With JodaTime

随着JodaTime

  LocalDate today = LocalDate.now();
    LocalDate yesterday = today.minus(Period.days(1));

    System.out.printf("Today is : %s, Yesterday : %s", today.toString("yyyy-MM-dd"), yesterday.toString("yyyy-MM-dd"));

#3

Convert the Date to a Calendar object and "roll" it back a single day. Something like this helper method take from here:

将日期转换为日历对象并将其“回滚”一天。像这个帮助方法的东西从这里采取：

public static void addDays(Date d, int days)
{
    Calendar c = Calendar.getInstance();
    c.setTime(d);
    c.add(Calendar.DATE, days);
    d.setTime(c.getTime().getTime());
}

For your specific case, just pass in days as -1 and you should be done. Just make sure you take into consideration the timezone/locale if doing extensive date specific manipulations.

对于您的具体情况，只需将日期作为-1传递，您应该完成。如果进行广泛的日期特定操作，请确保考虑时区/区域设置。

#4

you can try the follwing code:
Calendar cal = Calendar.getInstance();
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
System.out.println("Today's date is "+dateFormat.format(cal.getTime()));

cal.add(Calendar.DATE, -1);
System.out.println("Yesterday's date was "+dateFormat.format(cal.getTime()));

#5

As many people have already said use Calendar rather than date.

很多人已经说过使用Calendar而不是date。

If you find you really want to use dates:

如果您发现您真的想使用日期：

Calendar cal = Calendar.getInstance();
cal.add(Calendar.HOUR, -24);
cal.getTime();//returns a Date object

Calendar cal1 = Calendar.getInstance();
cal1.add(Calendar.DAY_OF_MONTH, -1);
cal1.getTime();//returns a Date object

I hope this helps. tomred

我希望这有帮助。 tomred

#6

You can try the following example to set it to previous date.

您可以尝试以下示例将其设置为上一个日期。

Calendar cal = Calendar.getInstance();
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy");
System.out.println("Today's date is " +dateFormat.format(cal.getTime()));    
cal.add(Calendar.DATE, -1);  
System.out.println("Yesterday's date was "+dateFormat.format(cal.getTime()));

#1