code: public void register(EventDefinition eventDefinition, IEventListener listener) {
          if (eventDefinition.getType() == EventDefinition.TYPE_POST) {
              register(listenersPost, eventDefinition, listener, true);
          } else {
              register(listeners, eventDefinition, listener, false);
          }
      }
docs: Start listening to an event.
  
  @param eventDefinition
  @param listener