public function increment($key, $offset = 1)
    {
        $filePath = $this->getFilePathFromKey($key);

        if (!file_exists($filePath)) {
            return false;
        }

        if (!is_readable($filePath)) {
            return false;
        }

        $cacheFileData = file_get_contents($filePath);

        if ($this->config['gzipCompression']) {
            $cacheFileData = gzuncompress($cacheFileData);
        }

        $cacheObj = json_decode($cacheFileData);
        $content = $cacheObj->content;

        if ($unserializedContent = @unserialize($content)) {
            $content = $unserializedContent;
        }

        if (!$content || !is_numeric($content)) {
            return false;
        }

        $content += $offset;

        return $this->set($key, $content, $cacheObj->expiryTimestamp);
    }