public function set($key, $value, $lifeTime = 900)
    {
        //~ Check if enabled
        if (!$this->isEnabled()) {
            return false;
        }

        //~ Clear expired Cache files
        $this->clearExpired();

        $pKey = $this->prefix() . $key;
        $file = $this->directory . substr(md5($pKey), 0, 10) . '.dat';
        if ((bool) file_put_contents($file, serialize($value))) {
            $this->cache[$pKey] = time() + $lifeTime;
            $this->save();

            return true;
        } else {
            return false;
        }
    }