To help make the ChatRoomService not need to know how the manager implements its chat room list, maybe we should have a size() method on the manager that would return the number of rooms being managed.  Then, this would just be this.chatRoomViewControllerManager.size() == 0.  That way, if you decide to change the chatRoomList from an Array to something else (for whatever reason), nothing outside of the ChatRoomViewController needs to be changed.