public function filter_output($item)
    {
        // filter out item if the name is not in "excluded" list
        if(!$this->is_allowed_name($item["attributes"]["name"], $item["type"] === self::TYPE_FOLDER)) {
            return false;
        }

        // filter out item if any filter is specified and item is matched
        $filter_name = isset($this->refParams['type']) ? $this->refParams['type'] : null;
        $allowed_types = isset($this->config['outputFilter'][$filter_name]) ? $this->config['outputFilter'][$filter_name] : null;
        if($filter_name && is_array($allowed_types) && $item["type"] === self::TYPE_FILE) {
            return (in_array(strtolower($item["attributes"]["extension"]), $allowed_types));
        }

        return true;
    }