question: private void filterNodeMap ( ConcurrentMap < String , Collection < ClusterNode > > map , final ClusterNode exclNode ) { for ( String cacheName : registeredCaches . keySet ( ) ) { String maskedName = maskNull ( cacheName ) ; while ( true ) { Collection < ClusterNode > oldNodes = map . get ( maskedName ) ; if ( oldNodes == null || oldNodes . isEmpty ( ) ) break ; Collection < ClusterNode > newNodes = new ArrayList < > ( oldNodes ) ; if ( ! newNodes . remove ( exclNode ) ) break ; if ( map . replace ( maskedName , oldNodes , newNodes ) ) break ; } } }
target:  Creates a copy of nodes map without the given node.