validate a youtube link and extract the video id

gistfile1.java

    public static boolean isYoutubeLink(String link) {
        link = link.trim();
        if (TextUtils.isEmpty(link)) return false;
        String pattern = "(http(?:s?):\\/\\/)?((?:www|m)(\\.))?youtu(?:be\\.com\\/watch\\?v=|\\.be\\/)([\\w\\-\\_]*)(&(amp;)?\u200C​[\\w\\?\u200C​=]*)?";
        return link.matches(pattern);
    }

    public static String extractYoutubeVideoId(String link) {
        link = link.trim();
        if (isYoutubeLink(link)) {
            Uri uri = Uri.parse(link);
            String host = uri.getHost();
            if (TextUtils.isEmpty(host)) {
                String[] split = link.split("/");
                host = split[0];
            }
            if (!TextUtils.isEmpty(host)) {
                host = host.toLowerCase();
            }
            if ("youtu.be".equals(host)) {
                return uri.getLastPathSegment();
            } else if ("youtube.com".equals(host)) {
                String last = uri.getLastPathSegment();
                if (!"watch".equals(host) && !"v".equals(host) && !"attribution_link".equals(host) && !"embed".equals(host)) {
                    return last;
                }
            }
            return uri.getQueryParameter("v");
        }
        return null;
    }