code: private String getEndpointBase(SharedPreferences prefs) {
  		String url = prefs.getString(Constants.PREF_KEY_SERVER_URL, null);
  		if (url == null) {
  			url = Constants.CONFIG_DEFAULT_SERVER_URL;
  			prefs.edit().putString(Constants.PREF_KEY_SERVER_URL, url).apply();
  		}
  		return url;
  	}
docs: region Helpers