使用AJAX请求分派器

Question

I'm sending a POST form using AJAX, and i'm trying to send back this value to my JSP, but I do not know exactly how to do it .

This is my AJAX.

 function ajax() {

    var e = document.getElementById("combo2");
    var e2 = e.options[e.selectedIndex].value;


    $.post( "MiddleContentApi", { cidades: e2})
        .done(function( data ) {
            alert( "Data Loaded: " + data );
        });
}

document.getElementById("okCity").addEventListener("click",ajax);

My Servlet :

   public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

    Integer cidadeId = Integer.parseInt(request.getParameter("cidades"));
      System.out.print(cidadeId);
    response.setContentType("text/html;charset=UTF-8");
    response.getWriter().write(String.valueOf(cidadeId));
}

Ajax is working totally ok, the value is returning to my "data" and the alert(data) is working either, but what I really need is to access this value returned using scriptles <% %> in jsp, but if I try to do something like :

      public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

      Integer cidadeId = Integer.parseInt(request.getParameter("cidades"));
          request.setAttribute("numero",cidadeId);
          RequestDispatcher rd = request.getRequestDispatcher("estados.jsp");
          rd.forward(request,response);

            }

This's just not working, and I can't acess the data in jsp by using :

   Object jbo = request.getAttribute("numero");

Does someone now how can I do this?