@Override
    public void redirectToProviderLoginPage(javax.servlet.http.HttpServletRequest request,
            javax.servlet.http.HttpServletResponse response, String originalRequest) throws
    LoginProviderException {
        RequestDispatcher dispatcher = request.getRequestDispatcher(forwardUrl);

        Map<String, String> params = new HashMap<>();

        params.put("param1", “value1”);
        params.put("param2", “value2”);

        request.setAttribute(“AuthParameters”, params);
        request.setAttribute(“ProviderGateURL”, “http://external.server.com/”);

        dispatcher.forward(request, response);
}