Case 1: Log out : Once we log out, if one tries to access previous, it must automatically redirect to login.jsp
Case 2: Session expired : If session expires when use
On login, set a cookie with a long expiry (> 24 hours). Remove this cookie at logout time by setting the maxage to 0.
You can have check for any non-logged in user (i.e. invalid session id). If the cookie does not exist, redirect him to login.jsp
If the cookie exists, it means his session expired so redirect him to session-expired.jsp