IT兄弟连 JavaWeb教程 JSP内置对象经典案例

案例需求：使用MVC模式编写一个程序当发起一个deptList.do请求时在servlet中准备一个部门列表对象，把这个列表对象放入request作用域中，然后转发到deptlist.jsp，使用jsp的语法来显示这个部门列表。部门类型是XdlDept成员变量有int id、String name、String loc。

案例实现：

●  XdlDept类

package com.xdl.bean;

import java.io.Serializable;

public class XdlDept  implements Serializable{

private static final long serialVersionUID = 1L;

@Override

public String toString() {

return "XdlDept [deptno=" + deptno + ", dname=" + dname

+ ", loc=" + loc + "]\n";

}

public XdlDept(int deptno, String dname, String loc) {

super();

this.deptno = deptno;

this.dname = dname;

this.loc = loc;

}

public XdlDept() {

super();

}

public int getDeptno() {

return deptno;

}

public void setDeptno(int deptno) {

this.deptno = deptno;

}

public String getDname() {

return dname;

}

public void setDname(String dname) {

this.dname = dname;

}

public String getLoc() {

return loc;

}

public void setLoc(String loc) {

this.loc = loc;

}

private  int  deptno;

private  String dname;

private  String  loc;

}

●  XdlDeptController类

package com.xdl.controller;

import java.io.IOException;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.xdl.bean.XdlDept;

import com.xdl.dao.XdlDeptDAO;

import com.xdl.dao.impl.XdlDeptDAOOracleImp;

@WebServlet("/deptList.do")

public class XdlDeptController extends HttpServlet {

private static final long serialVersionUID = 1L;

protected void service(HttpServletRequest request,

HttpServletResponse response) throws ServletException, IOException {

XdlDeptDAO  dao  =  new  XdlDeptDAOOracleImp();

// 通过M层获取数据

List<XdlDept>  depts = dao.getDeptList();

//放入对应的域对象

request.setAttribute("depts", depts);

// 跳转对应的页面

request.getRequestDispatcher("deptlist2.jsp").

forward(request, response);

}

}

●  deptList.jsp

<%@page import="com.xdl.bean.XdlDept"%>

<%@page import="java.util.ArrayList"%>

<%@page import="com.xdl.bean.XdlUser"%>

<%@page import="java.util.List"%>

<%@ page language="java" contentType="text/html; charset=utf-8"

pageEncoding="utf-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=utf-8">

<title>Insert title here</title>

<style type="text/css">

table {

width:600px;

text-align: center;

border-collapse: collapse;

}

table,tr,td{

border:1px solid red;

}

</style>

</head>

<body>

<%

// 这是单行注释

/** 这叫文档注释  */

List<XdlDept> datas2 = (List<XdlDept>)request.getAttribute("depts");

%>

<table>

<tr>  <td>DEPTNO</td> <td> DNAME</td> <td> LOC</td> </tr>

<%

for(int i=0;i<datas2.size();i++){

XdlDept  dept = datas2.get(i);

%>

<tr>

<td><%=dept.getDeptno() %></td>

<td><%=dept.getDname() %></td>

<td><%=dept.getLoc() %></td> </tr>

<%  }

%>

</table>

</body>

</html>