SSO/CAS intranet session to my Java EE portlet

I develop a jsp/servlet application that will be a "portlet" on intranet and I want that the user stay connect to his intranet CAS sessio开发者_如何学Gon and retrieve session informations to use in my application (like login).

If the user is not connected to CAS, I want to redirect to.

I use Spring in my java connections to LDAP and maybe I can found SSO/CAS session in this framework.

If anyone has a suggestion please say me, it's an urgent project...

EDIT: My application will be "portlet", integrate on a Jahia website which need to connect to CAS to access it

If this was a straight Servlet or JSP issue, I'd say that you should use Spring Security to handle the CAS integration (through spring-security-cas-client.jar as documented in the SpringSec docs).

However, you're using a Portlet framework which makes everything much more complex. You should check their documentation, as security is usually one of the things handled by the Portlet framework. (A quick scan of their admin docs isn't helpful; it seems entirely focused on password management rather than delegating it to a separate specialist service like CAS.)