code: public final void fireEvent(CalendarEvent evt) {
          if (fireEvents && !batchUpdates) {
              if (MODEL.isLoggable(FINER)) {
                  MODEL.finer(getName() + ": fireing event: " + evt); //$NON-NLS-1$
              }
  
              requireNonNull(evt);
              Event.fireEvent(this, evt);
          }
      }
docs: Fires the given calendar event to all event handlers currently registered
  with this calendar.
  
  @param evt the event to fire