question: private void retryFailedInterfaces ( ) { for ( Iterator i = failedInterfaces . iterator ( ) ; i . hasNext ( ) ; ) { NetworkInterface nic = ( NetworkInterface ) i . next ( ) ; try { if ( nic != null ) { socket . setNetworkInterface ( nic ) ; } socket . joinGroup ( requestAddr ) ; i . remove ( ) ; Level l = multicastInterfacesSpecified ? Level . INFO : Level . FINE ; if ( logger . isLoggable ( l ) ) { if ( nic != null ) { logger . log ( l , "enabled {0}" , new Object [ ] { nic } ) ; } else { logger . log ( l , "enabled default interface" ) ; } } } catch ( IOException e ) { } } }
target:  Attempts to configure each interface contained in the failedInterfaces list, removing it from the list if configuration succeeds.  The null value is used to indicate the default network interface.