无法使用会话保存数据

Question

嗨，我有这个网络应用程序，应该计算每个输入中编码的卡的总和。它很成功，但数据不会持久。这是我的代码。

控制器：

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    String BusName = "";
    String PlateNumber = "";
    String DriverAssigned = "";

    try{            
        BusName = request.getParameter("busName");
        PlateNumber = request.getParameter("plateNo");
        DriverAssigned = request.getParameter("driverAssigned");

        String firstString = PlateNumber.substring(0, 2);
        String secondString = PlateNumber.substring(3, 5);

        if (firstString.matches(".*[A-Z].*") && secondString.matches(".*\\d.*")){

        CalculatorBean beanCalc = BeanFactory.getInstance(BusName, PlateNumber, DriverAssigned);

        HttpSession session = request.getSession();
        session.setAttribute("deJesusBean", beanCalc);

        RequestDispatcher dispatcher = request.getRequestDispatcher("displayresult.jsp");

        dispatcher.forward(request, response);

我的逻辑模型：

public void compute(){
    char x = plateNo.charAt(5);

        if (x == '1' || x == '2'){
            dayOfCoding = "Monday";
            mondayCoding = mondayCoding + 1;
        }
        else if (x == '3' || x == '4'){
            dayOfCoding = "Tuesday";
            tuesdayCoding = tuesdayCoding + 1;
        }
        else if (x == '5' || x == '6'){
            dayOfCoding = "Wednesday";
            wednesdayCoding = wednesdayCoding + 1;
        }
        else if (x == '7' || x == '8'){
            dayOfCoding = "Thursday";
            thursdayCoding = thursdayCoding + 1;
        }
        else if (x == '9' || x == '0'){
            dayOfCoding = "Friday";
            fridayCoding = fridayCoding + 1;
        }
    }

我用它来显示它 ${deJesusBean.mondayCoding}

Answer 1

您需要删除会话或使会话无效，请尝试以下代码

HttpSession session = request.getSession();
if(session.getAttribute("deJesusBean") != null){
   session.removeAttribute("deJesusBean");
   session.setAttribute("deJesusBean", beanCalc);
}