question: private static final void cleanupSingleNamespaceNode ( ZooKeeper zkc , String path , String selfBrokerUrl ) throws Exception { String brokerUrl = null ; try { byte [ ] data = zkc . getData ( path , false , null ) ; if ( data . length == 0 ) { return ; } NamespaceEphemeralData zdata = jsonMapper . readValue ( data , NamespaceEphemeralData . class ) ; brokerUrl = zdata . getNativeUrl ( ) ; if ( selfBrokerUrl . equals ( brokerUrl ) ) { zkc . delete ( path , - 1 ) ; } } catch ( NoNodeException nne ) { } }
target:  cleanupSingleNamespaceNode is only called when the NamespaceService is initialized. So, no need for synchronization.