请教：servlet/jsp 问题

----------------goodsList.jsp  红色处没有显示数据

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
page Size : ${numbers}
<c:forEach items="${goodsList}" var="good">

${good.nnn}

</c:forEach>

 

 

 

 

--------------GoodListServlet.java

 

package soyo.shopping.servlet.admin;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import soyo.shopping.services.*;
import soyo.shopping.entity.Good;

public class GoodListServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    int numbers;
    public GoodListServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

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

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       
        GoodServices goodServices=new GoodServices();
        numbers = goodServices.getRecordNumber();

        List<Good> result=goodServices.getRecordAll();
        PrintWriter out = response.getWriter();

        request.setAttribute("goodsList", result);
        request.setAttribute("numbers", numbers);
        RequestDispatcher dispatcher=request.getRequestDispatcher("goodsList.jsp");
        dispatcher.forward(request, response);
    }

}

---------------Good.java

 

package soyo.shopping.entity;

public class Good {
    private String nnn;
   
    public Good(){
           
    }
   
    public Good(String nnn)
    {
        setGoodsNNN(nnn);
    }
   
    public String getGoodsNNN() {
        return nnn;
    }
    public void setGoodsNNN(String nnn) {
        this.nnn = nnn;
    }
}

 

 

 

报错信息为：

javax.servlet.jsp.el.ELException: Unable to find a value for "nnn" in object of class "soyo.shopping.entity.Good" using operator "."

不知道如何修改goodsList.jsp代码，望解答。

 

 

 

问题补充：
----------GoodServices.java

package soyo.shopping.services;

import java.util.List;
import soyo.shopping.dao.GoodDAO;
import soyo.shopping.entity.Good;

public class GoodServices {
GoodDAO goodDAO;

public GoodServices() {
goodDAO=new GoodDAO();
}

public int getRecordNumber(){
return goodDAO.getRecordNumber();
}
public List<Good> getRecordAll(){
List<Good> result=goodDAO.getRecordAll();
return result;
}

}


-----------------------GoodDAO.java
package soyo.shopping.dao;

import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.LinkedList;
import java.util.List;

import soyo.shopping.entity.Good;




public class GoodDAO {
Connection conn;
public GoodDAO(){
Init init=new Init();
conn=init.connent();
}

public int getRecordNumber(){
int count=0;
try {
Statement stmt = conn.createStatement();    
            ResultSet rs = stmt.executeQuery("select count(*) from goods");    
            System.out.println("PaginationDAO.getRecordNumber 12");
            while(rs.next()){
count=rs.getInt(1);
break;
            }
//destroy();
} catch (Exception e) {
System.err.println("PaginationDAO.getRecordNumber ERROR ## "+e.getMessage());
}
return count;
}

public List<Good> getRecordAll(){
List<Good> result=new LinkedList<Good>();
try {
Statement stmt = conn.createStatement();    
            ResultSet rs = stmt.executeQuery("select * from goods");    
            while(rs.next()){
            Good good = new Good(rs.getString("nnn"));
            result.add(good);
break;
            }
//destroy();
} catch (Exception e) {
System.err.println("PaginationDAO.getRecordNumber ERROR ## "+e.getMessage());
}
return result;
}

}



问题补充：
List<Good> result=goodServices.getRecordAll();
if(result.size()>0){

response.setHeader("Pragma","No-cache");
        response.setDateHeader("Expires",0);
        response.setHeader("Cache-Control","no-cache");
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        out.println("<h1>Hello,World!</h1>");
        out.println(result);
        out.println("<h1>Hello,World2!</h1>");
}



输出的结果是：

Hello,World!
[soyo.shopping.entity.Good@1e0512a]
Hello,World2!

public class Good {
private String nnn;

public Good(){

}

public Good(String nnn)
{
    setNnn(nnn);
}

public String getNnn() {
    return nnn;
}
public void setNnn(String nnn) {
    this.nnn = nnn;
}

}

把bean改成这样，你set和get好象有问题
这样后你.nnn
试下

get 和 set 方法不对吧

错误说无法找到nnn的对象，我问你下，你的

List result=goodServices.getRecordAll();

结果集返回的是对象吗？你debug下试试，如果这里面如果是2个对象的话那么你还需要再处理下

比如你的result中是个集合那么你需要把集合处理一下，这个很显然是你找不到属性嘛！把你getRecordAll();方法贴出来下

看方法到确实没什么问题是good一个对象
你将
List result=goodServices.getRecordAll();

if(result.size()>0){

}

看方法到确实没什么问题是good一个对象
你将
List result=goodServices.getRecordAll();

if(result.size()>0){
for(int i=0;i<result.size();i++){
System.out.println(result.get(i));
}

}

看看这样输出的是什么？

改成这样试试。

${good.goodsNnnn}

/c:forEach

java bean的规范，是根据你的get方法判断的名称的，不是按private 属性名的。