Java calander implementation

import java.util.*;

public class Main {

    public static void main(String args[])

    {

        TimeZone time_zone

            = TimeZone.getTimeZone("Pacific/Tahiti");

        Calendar calendar = Calendar.getInstance();

        calendar.setTimeZone(time_zone);

        System.out.println("Modified Zone: "

                           + calendar.getTimeZone()

.getDisplayName());

        System.out.println("The Current Date is:" + calendar.getTime());

        System.out.println("Current Calendar's Year: " + calendar.get(Calendar.YEAR));

        System.out.println("Current Calendar's Day: " + calendar.get(Calendar.DATE));

        System.out.println("Current MINUTE: " + calendar.get(Calendar.MINUTE));

        System.out.println("Current SECOND: " + calendar.get(Calendar.SECOND));

        calendar.add(Calendar.DATE, -15);

        System.out.println("15 days ago: " + calendar.getTime());

    }

}