Doctrine\Common\Cache\FileCache::doFlush PHP Method

    protected function doFlush()
    {
        foreach ($this->getIterator() as $name => $file) {
            if ($file->isDir()) {
                // Remove the intermediate directories which have been created to balance the tree. It only takes effect
                // if the directory is empty. If several caches share the same directory but with different file extensions,
                // the other ones are not removed.
                @rmdir($name);
            } elseif ($this->isFilenameEndingWithExtension($name)) {
                // If an extension is set, only remove files which end with the given extension.
                // If no extension is set, we have no other choice than removing everything.
                @unlink($name);
            }
        }
        return true;
    }