code: private void fireTangoPeriodicEvent(TangoPeriodic tangoPeriodic, EventData eventData) {
          TangoPeriodicEvent tangoPeriodicEvent = new TangoPeriodicEvent(tangoPeriodic, eventData);
          // Notifying those that are interested in this event
          ArrayList<EventListener> listeners = event_listeners.getListeners(ITangoPeriodicListener.class);
          for (EventListener eventListener : listeners) {
              ((ITangoPeriodicListener) eventListener).periodic(tangoPeriodicEvent);
          }
      }
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