protected function loadMessagesFromFile($messageFile, $category)
    {
        if (is_file($messageFile)) {
            if ($this->useMoFile) {
                $gettextFile = new GettextMoFile(['useBigEndian' => $this->useBigEndian]);
            } else {
                $gettextFile = new GettextPoFile();
            }
            $messages = $gettextFile->load($messageFile, $category);
            if (!is_array($messages)) {
                $messages = [];
            }

            return $messages;
        }

        return null;
    }