private void notifyUpdated(List<AirMapTraffic> updated){
  if (updated == null || updated.isEmpty()) {
    return;
  }
  for (  AirMapTrafficListener listener : listeners) {
    listener.onUpdateTraffic(updated);
  }
}

private void notifyUpdated ( List < AirMapTraffic > updated ) { if ( updated == null || updated . isEmpty ( ) ) { return ; } for ( AirMapTrafficListener listener : listeners ) { listener . onUpdateTraffic ( updated ) ; } }
notify the listeners that traffic has been updated
