/** {@inheritDoc} */
    public void additionalDataToReturnFromTokenEndpoint(
        AccessToken accessToken, OAuth2Request request)
        throws ServerException, InvalidClientException, NotFoundException {

      final Map<String, String> data = new HashMap<String, String>();
      data.put("nonce", accessToken.getNonce());
      data.put(
          OAuth2Constants.Custom.SSO_TOKEN_ID,
          getSsoToken(ServletUtils.getRequest(request.<Request>getRequest())));

      final Map<String, Object> tokenEntries =
          scopeValidator.extraDataToReturnForTokenEndpoint(
              data, new LegacyAccessTokenAdapter(accessToken));

      if (tokenEntries != null) {
        for (final Map.Entry<String, Object> tokenEntry : tokenEntries.entrySet()) {
          accessToken.addExtraData(tokenEntry.getKey(), (String) tokenEntry.getValue());
        }
      }
    }