public function setIsApi(string $is_api = "F") : CNabuDataObject
    {
        if ($is_api === null) {
            throw new ENabuCoreException(
                    ENabuCoreException::ERROR_NULL_VALUE_NOT_ALLOWED_IN,
                    array("\$is_api")
            );
        }
        $this->setValue('nb_language_is_api', $is_api);
        
        return $this;
    }