Serlvet方法裏面使用HttpServletRequest?request:?request.getRequestDispatcher()//重定向
public?void?login(HttpServletRequest?request){request.setAttribute("mes",?"登錄失敗");
request.getRequestDispatcher("login.jsp").forward(request,?null); }
前臺頁面(login.jsp):
<%=request.getAttribute("mes")%>