import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.TimeZone;
public class Main {
public static void main(String[] argv) throws Exception {
// Get the current time in Hong Kong
Calendar cal = new GregorianCalendar(TimeZone.getTimeZone("Hongkong"));
int hour12 = cal.get(Calendar.HOUR); // 0..11
int minutes = cal.get(Calendar.MINUTE); // 0..59
int seconds = cal.get(Calendar.SECOND); // 0..59
boolean am = cal.get(Calendar.AM_PM) == Calendar.AM;
// Get the current hour-of-day at GMT
cal.setTimeZone(TimeZone.getTimeZone("GMT"));
int hour24 = cal.get(Calendar.HOUR_OF_DAY); // 0..23
// Get the current local hour-of-day
cal.setTimeZone(TimeZone.getDefault());
hour24 = cal.get(Calendar.HOUR_OF_DAY); // 0..23
}
}