How do I do calendar arithmetic with java.util.Date?

Question

Currently I have a Date object representing a time. How would I add 5 minutes to this object?

Answer 1

Date has the time in milli-seconds. However, you might find using a long is simpler for this type of calculations.

Date date1 = new Date();
long time1 = date1.getTime();
long time2 = time1 + 5 * 60 * 1000;
Date date2 = new Date(time2);

If you use plain long you can drop the lines with Date objects.