code: public synchronized Iterable<IGenericEvent<T>> getSubscribers(String eventName) {
          List<IGenericEvent<T>> subscribers = getSubscribers(eventName, false);
          return subscribers == null ? null : new ArrayList<>(subscribers);
      }
docs: Returns a thread-safe iterable for the subscriber list.
  
  @param eventName Name of the event.
  @return Iterable for the subscriber list, or null if no list exists.