Java tutorial
import java.util.Date; import java.util.GregorianCalendar; /** * DateDiff -- compute the difference between two dates. */ public class DateDiff { public static void main(String[] av) { /** The date at the end of the last century */ Date d1 = new GregorianCalendar(2000, 11, 31, 23, 59).getTime(); /** Today's date */ Date today = new Date(); // Get msec from each, and subtract. long diff = today.getTime() - d1.getTime(); System.out.println( "The 21st century (up to " + today + ") is " + (diff / (1000 * 60 * 60 * 24)) + " days old."); } }