question: private Set < StoragePort > andNotStoragePorts ( Set < StoragePort > a , Set < String > b ) { Set < StoragePort > result = new HashSet < StoragePort > ( ) ; for ( StoragePort port : a ) { if ( ! b . contains ( port . getPortNetworkId ( ) ) ) { result . add ( port ) ; } } return result ; }
target:  Returns a AND (NOT b)