code: String getKey(URL remoteURL, String localUUID) {
          if (remoteURL == null)
              throw new IllegalArgumentException("remoteURL is null");
          String service = remoteURL.toExternalForm();
          String label = String.format(Locale.ENGLISH, "%s OpenID Connect tokens", remoteURL.getHost());
          if (localUUID == null)
              return String.format(Locale.ENGLISH, "%s%s", label, service);
          else
              return String.format(Locale.ENGLISH, "%s%s%s", label, service, localUUID);
      }
docs: /*package