public function is_valid() {
        $ret = false;

        if (is_null($this->division) === false && is_null($this->datafileURI) === false &&
            is_null($this->subscribe) === false && is_null($this->profileUpdate) === false &&
            is_null($this->listLoadName) === false && is_null($this->loadMode) === false &&
            is_null($this->headers) === false && is_null($this->maxErrors) === false &&
            is_null($this->errorType) === false
        ) {
            $ret = true;
        }

        return $ret;
    }