简化Java日期操作的开源项目DATE4J 超级好用

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以往要使用Java对时间日期进行操作，可能会用到以下的一些类：

Date and its subclasses :

• java.util.Date
• java.sql.Date
• java.sql.Timestamp

The calendar and time zone classes :

• java.util.Calendar
• java.util.GregorianCalendar
• java.util.TimeZone
• java.util.SimpleTimeZone (for use with the Gregorian calendar only)

The formatting and parsing classes :

• java.text.DateFormat
• java.text.SimpleDateFormat
• java.text.DateFormatSymbols

以上这么多类用起来是不是很麻烦呢，现在好了，有了DATE4J，就不用这么麻烦了。

下面是一些简单的实例：

[java] view plain copy print ?

1. //Examples  
2. //Here are some quick examples of using date4j's DateTime class :  
3. DateTime dateAndTime = new DateTime("2010-01-19 23:59:59");  
4. DateTime dateAndTime = new DateTime("2010-01-19 23:59:59.123456789");  
5. DateTime dateOnly = new DateTime("2010-01-19");  
6. DateTime timeOnly = new DateTime("23:59:59");  
7. DateTime dateOnly = DateTime.forDateOnly(2010,01,19);  
8. DateTime timeOnly = DateTime.forTimeOnly(23,59,59,0);  
9. DateTime dt = new DateTime("2010-01-15 13:59:15");  
10. boolean leap = dt.isLeapYear(); //false  
11. dt.getNumDaysInMonth(); //31  
12. dt.getStartOfMonth(); //2010-01-01, 00:00:00.000000000  
13. dt.getEndOfDay(); //2010-01-15, 23:59:59.999999999  
14. dt.format("YYYY-MM-DD"); //formats as '2010-01-15'  
15. dt.plusDays(30); //30 days after Jan 15  
16. dt.numDaysFrom(someDate); //returns an int  
17. dueDate.lt(someDate); //less-than  
18. dueDate.lteq(someDate); //less-than-or-equal-to  
19. //Although DateTime carries no TimeZone information internally, there are methods that take a TimeZone as a parameter :  
20. DateTime now = DateTime.now(someTimeZone);  
21. DateTime today = DateTime.today(someTimeZone);  
22. DateTime fromMilliseconds = DateTime.forInstant(31313121L, someTimeZone);  
23. birthday.isInFuture(someTimeZone);  
24. dt.changeTimeZone(fromOneTimeZone, toAnotherTimeZone);  

//Examples//Here are some quick examples of using date4j's DateTime class :DateTime dateAndTime = new DateTime("2010-01-19 23:59:59");DateTime dateAndTime = new DateTime("2010-01-19 23:59:59.123456789");DateTime dateOnly = new DateTime("2010-01-19");DateTime timeOnly = new DateTime("23:59:59");DateTime dateOnly = DateTime.forDateOnly(2010,01,19);DateTime timeOnly = DateTime.forTimeOnly(23,59,59,0);DateTime dt = new DateTime("2010-01-15 13:59:15");boolean leap = dt.isLeapYear(); //falsedt.getNumDaysInMonth(); //31dt.getStartOfMonth(); //2010-01-01, 00:00:00.000000000dt.getEndOfDay(); //2010-01-15, 23:59:59.999999999dt.format("YYYY-MM-DD"); //formats as '2010-01-15'dt.plusDays(30); //30 days after Jan 15dt.numDaysFrom(someDate); //returns an intdueDate.lt(someDate); //less-thandueDate.lteq(someDate); //less-than-or-equal-to//Although DateTime carries no TimeZone information internally, there are methods that take a TimeZone as a parameter :DateTime now = DateTime.now(someTimeZone);DateTime today = DateTime.today(someTimeZone);DateTime fromMilliseconds = DateTime.forInstant(31313121L, someTimeZone);birthday.isInFuture(someTimeZone);dt.changeTimeZone(fromOneTimeZone, toAnotherTimeZone);

 

获取DATE4J.jar请访问DATE4J项目网站：http://www.date4j.net

           

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