Exception in JSP: /jpk/course/layout/lesson/notice3.jsp:31 28: //传参 29: Long nLessID = (Long) session.getAttribute("lid"); 30: if (nLessID == null) { 31: throw new Exception(appContext.getMessage("error.info.classification.import", null, request.getLocale())); 32: } 33: 34: ElaCourseService service = (ElaCourseService) ZyAppContext.getBean("elaCourseService"); Stacktrace:！