Java tutorial
import java.util.Calendar; public class Main { public static void main(String[] args) { Calendar cal = Calendar.getInstance(); // display the current calendar System.out.println("Month is " + cal.get(Calendar.MONTH)); // roll month cal.roll(Calendar.MONTH, 2); // print result after rolling System.out.println("Month is " + cal.get(Calendar.MONTH)); // roll downwards cal.roll(Calendar.MONTH, -4); // print result System.out.println("Month is " + cal.get(Calendar.MONTH)); } }