java - 显示标签在jsp中不显示详细信息

Question

无法在我的显示标记中获取 bean 的值..显示以下错误

  String sql;
        List<AcceptBean> list = new ArrayList<AcceptBean>();

        PreparedStatement prest = (PreparedStatement) conn.prepareStatement(occQuery);
        ResultSet rs = prest.executeQuery(occQuery);

        System.out.println(rs);
        String first = "";
        String last = "";
        String vill = "";
        String son = "";
        String dist = "";
        while (rs.next()) {

           AcceptBean bean = new AcceptBean();

           bean.setFirstName(rs.getString("FirstName"));

           bean.setLastName(rs.getString("LastName"));
           bean.setVillage(rs.getString("Village"));
           bean.setSonOf(rs.getString("SonOf"));
           bean.setDistrict(rs.getString("District"));
           list.add(bean);
}

       // list.add(objBean);
        System.out.println("list vlues in servelet" + list.get(0));
        System.out.println("list detials inserted");
        request.setAttribute("list1", list);

        ServletContext context = getServletContext();
        RequestDispatcher rd = context.getRequestDispatcher("/Report.jsp");
        System.out.println("request dispatched");
        rd.forward(request, response);

这是我的jsp代码

    <display:table name="requestScope.list1"  >
               <display:column property="firstname" title="First Name"></display:column>
                <display:column property="lastname" title="Last Name"   ></display:column>
                <display:column property="sonof" title="Father's Name"  ></display:column>
                <display:column property="district" title="District"  ></display:column>
                <display:column property="village" title="Village"  ></display:column>
            </display:table>

错误异常:[.LookupUtil] 在对象类型“ColdStorage.AcceptBean”中查找属性“firstname”时出错。原因:类“class ColdStorage.AcceptBean”上的未知属性“firstname”

Answer 1

1. 当然。如果不能将对象放入列表中，那么列表还有什么意义呢？它应该被声明并初始化为

   List<AcceptBean> list = new ArrayList<AcceptBean> 
   

   不过。

2. 问题是您告诉标记在名为“list”的请求属性中查找列表，但它存储在名为“list1”的请求属性中。

3. 就像您所做的那样，当然您应该在 wile 循环内创建一个新的 AcceptBean，并将其添加到 while 循环内的列表中。否则，列表中只会有一个对象，其中包含从数据库检索到的最后一行:

   List<AcceptBean> list = new ArrayList<AcceptBean>();
   
   PreparedStatement prest = (PreparedStatement) conn.prepareStatement(occQuery);
   ResultSet rs = prest.executeQuery();
   while (rs.next()) {
       AcceptBean bean = new AcceptBean();
       bean.setFirstName(rs.getString("FirstName"));
       bean.setLastName(rs.getString("LastName"));
       bean.setVillage(rs.getString("Village"));
       bean.setSonOf(rs.getString("SonOf"));
       bean.setDistrict(rs.getString("District"));
       list.add(bean);
   }
   
   request.setAttribute("list1", list);
   

4. 没有。你为什么不阅读标签文档呢？它解释了如何使用它、属性是什么，并包含大量示例。

5. 参见上文。