code: private synchronized ApptentiveNotificationObserverList resolveObserverList(String name) {
  		ApptentiveNotificationObserverList list = observerListLookup.get(name);
  		if (list == null) {
  			list = new ApptentiveNotificationObserverList();
  			observerListLookup.put(name, list);
  		}
  		return list;
  	}
docs: Find an observer list for the specified name or creates a new one if not found.