JBoss.org Community Documentation The destroy(ObjectName) method

The destroy(ObjectName) method is called whenever an event occurs that affects the named services state. This could be triggered by an explicit invocation by the SARDeployer, notification of a class removal, or a service on which other services depend reaching its destroyed state.

Service implementations often do not implement destroy in favor of simply implementing the stop method, or neither stop nor destroy if the service has no state or resources that need cleanup.