Java tutorial
import java.util.Calendar; public class DateAddHour { public static void main(String[] args) { Calendar calendar = Calendar.getInstance(); System.out.println("Original = " + calendar.getTime()); // Subtract 2 hour from the current time calendar.add(Calendar.HOUR, -2); // Add 30 minutes to the calendar time calendar.add(Calendar.MINUTE, 30); // Add 300 seconds to the calendar time calendar.add(Calendar.SECOND, 300); System.out.println("Updated = " + calendar.getTime()); } }