private List<String> extractUrlsSameHost(List<String> urls) {

        List <String> urlsRes = new ArrayList<String>();

        // 元のURLのホスト文字列を取得する
        String hostOrig = "";
        URL resourceOrig;
        try {
            resourceOrig = new URL(Process.getUrlOrig());
            hostOrig = resourceOrig.getHost();
        } catch (MalformedURLException e1) {
            e1.printStackTrace();
            logger.severe("Couldn't get info from the url: " + Process.getUrlOrig());
            System.exit(1);
        }

        // urlsNotAccessをループ処理する
        URL resource;
        String host;
        for (String url: urls) {
            try {
                // urlのホスト名を抜き出す
                resource = new URL(url);
                host = resource.getHost();
                if (host.equals(hostOrig)) {
                    urlsRes.add(url);
                }
            } catch (MalformedURLException e) {
                //e.printStackTrace();
                logger.warning("Couldn't get info from the url: " + url);
                continue;
            }
        }
        return urlsRes;
    }