How set and get parameter for a session of a portlet (Java)

Question

I would like get parameter and set parameter for a portlet in portal 9.02. This parameter must be availbale during the session of the portal.
With Java Servlet
// I retrieve my session
HttpServletRequest httpreq = (HttpServletRequest)req;
HttpServletResponse httpresp = (HttpServletResponse)resp;
HttpSession session = httpreq.getSession();
//And after i can get or set some parameter for this servlet
//Example
session.setAttribute("MyEmployeeNumber","600000");
String id = (String)session.getAttribute("MyEmployeeNumber");
// But with Portlet in portal, i can't do it.
PortletRenderRequest pr= (PortletRenderRequest)httpreq.getAttribute(HttpCommonConstants.PORTLET_RENDER_REQUEST);
String sUser=pr.getUser().getName();
ProviderSession session=pr.getSession();
// But after if i want get or set a value in this session i have a internal error 500
session.setAttribute("MyEmployeeNumber","600000");
I would like my parameter is avalaible during a session for a user in each page of the portal, because my portlet is on each page.

Answer 1

I have almost the same problem. I tried as you suggested, but it doesn't work yet.
provider.xml
<session>true</session>
<passAllUrlParams>true</passAllUrlParams>
My code in my jsp-portlet is
<%@page contentType="text/html; charset=windows-1252"
import="oracle.portal.provider.v2.render.PortletRenderRequest"
import="oracle.portal.provider.v2.render.PortletRendererUtil"
import="oracle.portal.provider.v2.http.HttpCommonConstants"
import="oracle.portal.provider.v2.ParameterDefinition"
import="oracle.portal.provider.v2.render.http.HttpPortletRendererUtil"
%>
<%@page session="true"%>
<%
PortletRenderRequest pReq = (PortletRenderRequest)request.getAttribute(HttpCommonConstants.PORTLET_RENDER_REQUEST);
String valueSession = (String)pReq.getAttribute("sesion");
if (valueSession != null) {
pReq.setAttribute("session", "value1");
out.println("<br>(1)valueSession != null");
out.println("<br>(1)valueSession : " + pReq.getAttribute("session"));
} else {
pReq.setAttribute("session", "value2");
out.println("<br>(2)valueSession == null");
out.println("<br>(2)valueSession : " + pReq.getAttribute("session"));
%>
And i always get as result:
(2)valueSession == null
(2)valueSession : value2
Even when i send values (post) at the same page or browsing between tabs:
I check my provider registration and it has the value "once per session"
I have portal 9.0.2.2.14
Thanks