question: private void validateStorageUnitNotificationRegistrationKey ( NotificationRegistrationKey notificationRegistrationKey ) throws IllegalArgumentException { Assert . notNull ( notificationRegistrationKey , "A storage unit notification registration key must be specified." ) ; notificationRegistrationKey . setNamespace ( alternateKeyHelper . validateStringParameter ( "namespace" , notificationRegistrationKey . getNamespace ( ) ) ) ; notificationRegistrationKey . setNotificationName ( alternateKeyHelper . validateStringParameter ( "notification name" , notificationRegistrationKey . getNotificationName ( ) ) ) ; }
target:  Validates the storage unit notification registration key. This method also trims the key parameters.