* @param string $eventName preferably the fully-qualified class name of the Event sub class to listen for
* @param string $eventName preferably the fully-qualified class name of the Event sub class to listen for
* @param string $className fully qualified class name (or ::class notation) of a \OCP\EventDispatcher\IEventListener that can be built by the DI container
* @param string $className fully qualified class name (or ::class notation) of a \OCP\EventDispatcher\IEventListener that can be built by the DI container