question: @ Override public void clear ( ) { if ( server != null ) { QueryExp exp = Query . eq ( Query . attr ( "coreHashCode" ) , Query . value ( coreHashCode ) ) ; Set < ObjectName > objectNames = null ; try { ObjectName instance = new ObjectName ( jmxRootName + ":*" ) ; objectNames = server . queryNames ( instance , exp ) ; } catch ( Exception e ) { log . warn ( "Exception querying for mbeans" , e ) ; } if ( objectNames != null ) { for ( ObjectName name : objectNames ) { try { server . unregisterMBean ( name ) ; } catch ( Exception e ) { log . warn ( "Exception un-registering mbean {}" , name , e ) ; } } } } super . clear ( ) ; }
target:  Clears the map and unregisters all SolrInfoMBeans in the map from MBeanServer