static {
BAD_HOSTS = new Pattern[]{Pattern.compile("(\\W|\\b)telegram(\\.\\w+){1,2}\\z", 2)};
}

public static boolean isBadHost(String urlStr) {
if (urlStr == null) {
return true;
}
try {
String host = new URL(makeUrl(urlStr)).getHost().toLowerCase();
for (Pattern badHost : BAD_HOSTS) {
if (badHost.matcher(host).find()) {
return true;
}
}
return false;
} catch (MalformedURLException e) {
return true;
}
}