question: private void validateMessage ( String expectedType , String type , long returnCode , String service , String payload ) throws ReplicatorException { if ( ! type . equals ( expectedType ) ) { throw new ReplicatorException ( "Server should have returned message of type \"" + Protocol . TYPE_FILTERED + "\", but returned \"" + type + "\" instead" ) ; } else if ( returnCode != 0 ) { throw new ReplicatorException ( "Server returned a non-zero code (" + returnCode + "), payload: " + payload ) ; } else if ( ! service . equals ( messageGenerator . getService ( ) ) ) { throw new ReplicatorException ( "Server returned unexpected service name in the message: received \"" + service + "\", but expected \"" + messageGenerator . getService ( ) + "\"" ) ; } }
target:  Protocol safety checks for the server returned message.