private void notifyAdded(List<AirMapTraffic> added){
  if (added == null || added.isEmpty()) {
    return;
  }
  for (  AirMapTrafficListener listener : listeners) {
    listener.onAddTraffic(added);
  }
}

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