How to Add or Subtract Date in Java

The java.util.Calendar allows us to do a date arithmetic function such as add or subtract a unit of time to the specified date field.


The method that done this process is the Calendar.add(int field, int amount). Where the value of the field can be Calendar.DATE, Calendar.MONTH, Calendar.YEAR. So this mean if you want to subtract in days, months or years use Calendar.DATE, Calendar.MONTH or Calendar.YEAR respectively.

The complete source code is given below:

import java.util.Calendar;

public class CalendarAddExample {
 public static void main(String[] args) {

  Calendar cal = Calendar.getInstance();

  System.out.println("Today : " + cal.getTime());

  // Subtract 30 days from the calendar

  cal.add(Calendar.DATE, -30);
  System.out.println("30 days ago: " + cal.getTime());

  // Add 10 months to the calendar

  cal.add(Calendar.MONTH, 10);
  System.out.println("10 months later: " + cal.getTime());

  // Subtract 1 year from the calendar

  cal.add(Calendar.YEAR, -1);
  System.out.println("1 year ago: " + cal.getTime());
 }
}

The output is


Today : Sat Jul 21 23:18:43 IST 2012
30 days ago: Thu Jun 21 23:18:43 IST 2012
10 months later: Sun Apr 21 23:18:43 IST 2013
1 year ago: Sat Apr 21 23:18:43 IST 2012




The links that may help you:



How to Add or Subtract time using Calendar in Java
Add or subtract weeks to current date using Java Calendar