src/Auth/AuthAPI.php
private function setDefaultLanguage($userId) {
        if ($this->language !== null) {
            $languageModel = new \Mmf\Language\LanguageModel($this->connection);
            $userLanguageProperties = $languageModel->getUserLanguage($userId);
            if ($userLanguageProperties !== false) {
                $this->language->setLocale($userLanguageProperties['code']);
            }
        }
    }
private function setDefaultLanguage($userId) {
        if ($this->language !== null) {
            $languageModel = new \Mmf\Language\LanguageModel($this->connection);
            $userLanguageProperties = $languageModel->getUserLanguage($userId);
            if ($userLanguageProperties !== false) {
                $this->language->setLocale($userLanguageProperties['code']);
            }
        }
    }
Set the default language for this user.

@param int $userId