問題描述
我知道這里也有同樣的問題，但我試過了提供的答案，它返回了一個我不明白的輸出.我對答案感到困惑，我認為輸出不正確.
I know there is the same question here, but I have tried the answer provided and it returned an output that I don't understand. I am confused by the answer and I don't think the output is correct.
我需要幫助，謝謝:)
GregorianCalendar date1 = new GregorianCalendar( 2014, 05, 12 ); //05 is june as month start from 0 -11
while( date1.get( Calendar.DAY_OF_WEEK ) != Calendar.MONDAY )
date1.add( Calendar.DATE, 1 );
System.out.println(date1);
這是輸出:
java.util.GregorianCalendar[time=1405267200000,areFieldsSet=true,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Asia/Singapore",offset=28800000,dstSavings=0,useDaylight=false,transitions=9,lastRule=null],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=2014,MONTH=6,WEEK_OF_YEAR=29,WEEK_OF_MONTH=3,DAY_OF_MONTH=14,DAY_OF_YEAR=195,DAY_OF_WEEK=2,DAY_OF_WEEK_IN_MONTH=2,AM_PM=0,HOUR=0,HOUR_OF_DAY=0,MINUTE=0,SECOND=0,MILLISECOND=0,ZONE_OFFSET=28800000,DST_OFFSET=0]
我應該提取輸出的哪個位置來檢索星期一的日期?
Where on the output should I extract to retrieve Monday's date?
推薦答案
Java 8+
LocalDate ld = LocalDate.of(2014, Month.JUNE, 12);
System.out.println(ld);
ld = ld.with(TemporalAdjusters.next(DayOfWeek.MONDAY));
System.out.println(ld);
哪些打印...
2014-06-12
2014-06-16
因為我的實際日期可能是星期一，所以您也可以使用...
Because it's possible that the date my actually be a Monday, you could also use...
ld = ld.with(TemporalAdjusters.nextOrSame(DayOfWeek.MONDAY));
Java <= 7
您應該使用 ThreeTen Backport，它為您提供 Java 8 Date/的支持時間接口
Java <= 7
You should be using the ThreeTen Backport, which gives you the support of the Java 8 Date/Time API
代替 System.out.println(date1); 使用 System.out.println(date1.getTime());
getTime 返回一個 Date 的實例，它表示 Calendar
getTime returns an instance of Date which represents the current state of the Calendar
這將輸出 Mon Jul 14 00:00:00 EST 2014
System.out.println(date1) 等價于使用 System.out.println(date1.toString())，在本例中為轉儲一堆關于 Calendar 對象狀態的有用信息，但不是真正的人類可讀數據.
System.out.println(date1) is the equivlent of using System.out.println(date1.toString()), which, in this case, is dumping a bunch of useful info about the state of the Calendar object, but not really human readable data.
System.out.println(date1.getTime()) 將使用 Date 的 to toString 方法來顯示日期值, 根據當前的本地設置格式化，這將提供更多有用的信息.
System.out.println(date1.getTime()) will use the Date's to toString method to display a date value, formatted based on the current local settings, which will provide more useful information.
更新
不要使用GregorianCalendar，而應該使用系統Calendar，例如...
Instead of using GregorianCalendar, you should use the system Calendar, for example...
Calendar date1 = Calendar.getInstance();
date1.set(2014, 06, 12);
此外，月份是 0 索引的，這意味著 Janurary 實際上是 0 而不是 1，因此在您的示例中，您指定了月份為 7 月，而不是 6 月.
Also, months are 0 indexed, meaning that Janurary is actually 0 not 1, so in your example, you've specified the month as July, not June.
所以，相反，使用...
So, instead, using...
Calendar date1 = Calendar.getInstance();
date1.set(2014, 05, 12);
while (date1.get(Calendar.DAY_OF_WEEK) != Calendar.MONDAY) {
date1.add(Calendar.DATE, 1);
}
System.out.println(date1.getTime());
哪個輸出了...
Mon Jun 16 16:22:26 EST 2014
從今天開始是下周一...或多或少 ;)
Which is next Monday from today...more or less ;)
這篇關于在特定日期之后的下周一獲得第一個?的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！