question: public void preDeregister ( ) throws Exception { try { close ( ) ; if ( ! sequencer . tryAcquire ( ) ) throw new IllegalStateException ( "can't acquire lock" ) ; try { unregisterScanners ( ) ; unregisterConfigs ( ) ; unregisterResultLogManager ( ) ; } finally { sequencer . release ( ) ; } } catch ( Exception x ) { LOG . log ( Level . FINEST , "Failed to unregister: " + x , x ) ; throw x ; } }
target:  Allows the MBean to perform any operations it needs before being unregistered by the MBean server. This implementation also unregisters all the MXBeans that were created by this object.