protected function getFromCache($src)
	{
		$differentiator = $this->getCacheDifferentiator();
		$key            = sha1(serialize([get_class($this), $differentiator, $src]));
		$cacheFile      = $this->cacheDir . '/minifier.' . $key . '.js';

		if (!file_exists($cacheFile))
		{
			file_put_contents($cacheFile, $this->minify($src));
		}

		return file_get_contents($cacheFile);
	}