code: public static Object getSessionValue(HttpServletRequest request, String key) {
  
          HttpSession session = request.getSession(true);
          return session.getAttribute(key);
      }
docs: Reads an object from the session of the given HTTP request.<p>
  
  A session will be initialized if the request does not currently have a session.
  As a result, the request will always have a session after this method has been called.<p>
  
  Will return <code>null</code> if no corresponding object is found in the session.<p>
  
  @param request the request to get the session from
  @param key the key of the object to read from the session
  @return the object received form the session, or <code>null</code>