are there any methods in java for date computations?

Question

are there any functions in comparing and subtracting Dates in Java

example
june 10,2007
- june 5, 2007
____________
5 days

Answer 1

The Calendar class is where most date manipulation is done, but there aren't built-in methods for "number of days from" (another Calendar).

More or less, you have to write it yourself. A couple of ways:

(1) Get the millisecond clock values from two different Calendars, and divide by (1000*60*60*24). This works for most cases, but might get tripped up by the switch to/from Daylight Savings Time (because Midnight July 1 is not an even multiple of 24 hours from Midnight December 1).

(2) Get the day of the year (c.get( Calendar.DAY_OF_YEAR)) from each Calendar, and subtract... but you'll have to code for proper handling of the case where the two Calendars are in different years.

Answer 2

You may also want to check out the calendar class

Answer 3

http://java.sun.com/j2se/1.4.2/docs/api/java/util/Date.html