这是一个数据访问方法GoodsDao,javabean就不写了
public List<Goods> selectAllGoods(){
List<Goods> list=new ArrayList<Goods>();
try{
stmt=con.prepareStatement("select * from goods");
ResultSet rs=stmt.executeQuery();
while(rs.next()){
Goods good=new Goods();
good.setGoods_id(rs.getString(1));
good.setGoods_name(rs.getString(2));
good.setGoods_price(rs.getFloat(3));
good.setPicture(rs.getString(4));
list.add(good);
}
}catch(Exception e){}
return list;
}
用主方法可以读出记录
public static void main(String[] args) {
GoodsDao gd=new GoodsDao();
System.out.print(gd.selectAllGoods().get(4).getGoods_price());
}
但是用jsp就出错或者得不到结果
<%@ page contentType="text/html;charset=GB2312"%><%@ page import="cart.bean.Goods" %>
<%@ page import="cart.dao.GoodsDao" %>
<%@page import="java.util.*;"%>
<jsp:useBean id="good" class="cart.bean.Goods" scope="session" />
<html>
<head>
<title>购物首页</title>
</head>
<body>
<%
GoodsDao gd=new GoodsDao();
good=gd.selectAllGoods().get(1);
out.print(good.getGoods_price());
%>
</body>
</html>
该如何正确显示,求解决
public List<Goods> selectAllGoods(){
List<Goods> list=new ArrayList<Goods>();
try{
stmt=con.prepareStatement("select * from goods");
ResultSet rs=stmt.executeQuery();
while(rs.next()){
Goods good=new Goods();
good.setGoods_id(rs.getString(1));
good.setGoods_name(rs.getString(2));
good.setGoods_price(rs.getFloat(3));
good.setPicture(rs.getString(4));
list.add(good);
}
}catch(Exception e){}
return list;
}
用主方法可以读出记录
public static void main(String[] args) {
GoodsDao gd=new GoodsDao();
System.out.print(gd.selectAllGoods().get(4).getGoods_price());
}
但是用jsp就出错或者得不到结果
<%@ page contentType="text/html;charset=GB2312"%><%@ page import="cart.bean.Goods" %>
<%@ page import="cart.dao.GoodsDao" %>
<%@page import="java.util.*;"%>
<jsp:useBean id="good" class="cart.bean.Goods" scope="session" />
<html>
<head>
<title>购物首页</title>
</head>
<body>
<%
GoodsDao gd=new GoodsDao();
good=gd.selectAllGoods().get(1);
out.print(good.getGoods_price());
%>
</body>
</html>
该如何正确显示,求解决
放到<body></body>中去 这是标签啊
<jsp:useBean id="good" class="cart.bean.Goods" scope="session" />
<%@ page contentType="text/html;charset=GB2312"%>
<%@ page import="cart.bean.Goods" %>
<%@ page import="cart.dao.GoodsDao" %>
<%@page import="java.util.*;"%>
<html>
<head>
<title>购物首页</title>
</head>
<body>
<%
GoodsDao gd=new GoodsDao();
System.out.print(gd.selectAllGoods().get(4).getGoods_price());
%>
</body>
</html>楼主试试看,为什么非要用jsp:useBean呢!
An exception occurred processing JSP page
没有get()方法的都会返回0,或者null
放到服务器里之后的conn又是怎么得到的呢?有没有差异?good luck
import java.sql.*;public class DBConnection {
public Connection con=null;
public DBConnection(){
try{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
con=DriverManager.getConnection("jdbc:sqlserver://localhost:1433;DatabaseName=bookstore","sa","123");
}catch(Exception e){
}
}
}这是个连接,然后就是
public class GoodsDao {
Connection con;
PreparedStatement stmt;
DBConnection dbc;
public GoodsDao(){
dbc=new DBConnection();
con=dbc.con;
}
public List<Goods> selectAllGoods(){
List<Goods> list=new ArrayList<Goods>();
try{
stmt=con.prepareStatement("select * from goods");
ResultSet rs=stmt.executeQuery();
while(rs.next()){
Goods good=new Goods();
good.setGoods_id(rs.getString(1));
good.setGoods_name(rs.getString(2));
good.setGoods_price(rs.getFloat(3));
good.setPicture(rs.getString(4));
list.add(good);
}
}catch(Exception e){}
return list;
}
最后就是jsp了
比如tomcat/lib下或者webapps/XXX/WEB-INF/lib下面?good luck