UnknownFileException example

/** * @param int $shopId * * @throws UnknownFileException * * @return bool */
    private function closeFile($shopId)
    {
        if (!\array_key_exists($shopId, $this->files)) {
            throw new UnknownFileException(sprintf('No open file "%s"', $shopId));
        }

        $fileHandle = $this->files[$shopId]['fileHandle'];
        $this->write($fileHandle, '</urlset>');

        gzclose($fileHandle);

        if (!\array_key_exists($shopId, $this->sitemaps)) {
            $this->sitemaps[$shopId] = [];
        }