No subject

 Setting the session attribute:

  public void service(HttpServletRequest request, HttpServletResponse
response) {
	 //...your code
	 request.getSession().setAttribute("arbitary_attribute_name",
yourObjectInstance);
       //...the rest of your code
  }

 Retrieving your object from the session:

 public void service(HttpServletRequest request, HttpServletResponse
response) {
	 //...your code
      YourObject yourObjectInstance =
(YourObject)request.getSession().getAttribute("arbitary_attribute_name");
	//...the rest of your code
 }