public function setExpiry(int $expiry = 604800) : CNabuDataObject
    {
        if ($expiry === null) {
            throw new ENabuCoreException(
                    ENabuCoreException::ERROR_NULL_VALUE_NOT_ALLOWED_IN,
                    array("\$expiry")
            );
        }
        $this->setValue('nb_domain_zone_expiry', $expiry);
        
        return $this;
    }