Several notifications are sent from admin server instance to administered server instance(s). The notification is in the form of a event. There are four categories of events - Deployment, Monitoring, ConfigurationChange and Shutdown.
Deployment events are for applications, stand alone modules and resources and are raised whenever something is undeployed, redeployed, deployed, enabled or disabled. Monitoring Events are used to start and stop monitoring, to get monitoring data and to list monitorable components. ConfigurationChange events are raised whenever there is an apply action on UI for all changes that can not be categorized as Deployment or Monitoring event. ShutdownEvent is there because it was in functional specification, but it is unlikely to be used.
The method multicastEvent() in the class AdminEventMulticaster can be used to multicast events (to all listeners in appropriate administered server instance).
The various register methods in the class AdminEventListenerRegistry can be used to register listeners for a event.