@At("queryTeacher")
    @Ok("jsp:show")
    public void QueryTeacher(HttpServletRequest request,HttpSession session){
        List<Teacher> teacherList = dao.query(Teacher.class, null);
        Teacher teacher2=new Teacher();
        for (Teacher teacher1 : teacherList){

            int lessId = teacher1.getLessId();
            teacher2.setLessId(lessId);
        }
        session.setAttribute("lessonid",teacher2);
        request.setAttribute("teacherlist",teacherList);
@At("deletelesson")
    @Ok(">>:queryTeacher")
    public boolean DeleteLesson(HttpServletRequest request, HttpSession session){
        int lessonid = Integer.parseInt(String.valueOf(session.getAttribute("lessonid")));
        Lesson lesson = dao.fetchLinks(dao.fetch(Lesson.class, lessonid), "students");
        request.setAttribute("lesson",lesson);
        return true;
    }