get session null in custom portal app

hi everyone.

I migrated a project sap portal app 7.0 to 7.4 but when I deploy I got a session is null with name “vendorCode”  my code below:

IPortalComponentSession compSession = request.getComponentSession();

javax.servlet.http.HttpSession httpSession = null;

httpSession = compSession.getHttpSession();

if(httpSession != null&& httpSession.getAttribute("vendorCode") != null)

{

vCode = (String)httpSession.getAttribute("vendorCode").toString();

}

httpSession.getAttribute("vendorCode") has always null

Where we get from “vendorCode” ? is it get from properties iview and we can configure iview properties with nam  “vendorCode” ?