[求助]Action与jsp的传值问题

List dwclassdesclist=null;
public ActionForward execute(
ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response) throws Exception{
String dwclassid = request.getParameter("dwclassid");
DwSelectForm dwSelectForm=(DwSelectForm)form;
if (dwclassid==null){
List dwClassList = getDwList();
dwSelectForm.setDwclassList(dwClassList);
if(dwClassList.size()>0){
return mapping.findForward("refresh");
}else{
return mapping.findForward("success");
}
}else{
DwClassService dwClassService = (DwClassService) ServiceManager
.getInstance().getService("dwClassService");
DwClass dwClass=dwClassService.findByID(dwclassid);
request.getSession().setAttribute(Constants.SYS_DWSELECTED,dwClass);
request.setAttribute("dwclassdesclist", dwclassdesclist);
return mapping.findForward("success");
}


怎么在JSP页面里获得dwclassdesclist