springMvc-视图模型封装及注解参数

1.视图模型封装，ModelAndView可以向页面返回视图的同时吧模型也传入页面

2.注解参数，springMvc很好的地方在于简单，高效，@RequestParam注解能非常好的取得页面参数

代码：

1.创建model

package com.java1234.model;

public class Student {

private int id;
private String name;
private int age;

public Student() {
super();
// TODO Auto-generated constructor stub
}

public Student(int id, String name, int age) {
super();
this.id = id;
this.name = name;
this.age = age;
}

public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}

}

2.创建controller

package com.java1234.controller;

import java.util.ArrayList;
import java.util.List;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

import com.java1234.model.Student;

@Controller
@RequestMapping("/student")
public class StudentController {

private static List<Student> studentList=new ArrayList<Student>();

static{
studentList.add(new Student(1,"张三",11));
studentList.add(new Student(2,"李四",12));
studentList.add(new Student(3,"王五",13));
}

@RequestMapping("/list")
public ModelAndView list(){
ModelAndView mav=new ModelAndView();
mav.addObject("studentList", studentList);
mav.setViewName("student/list");
return mav;
}

@RequestMapping("/preSave")
public ModelAndView preSave(@RequestParam(value="id",required=false) String id){
ModelAndView mav=new ModelAndView();
if(id!=null){
mav.addObject("student", studentList.get(Integer.parseInt(id)-1));
mav.setViewName("student/update");
}else{
mav.setViewName("student/add");
}
return mav;
}
}

3.页面向controller提交参数：

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!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>
</head>
<body>
<a href="${pageContext.request.contextPath}/student/preSave.do">添加学生</a>
<table>
<tr>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
<th>操作</th>
</tr>
<c:forEach var="student" items="${studentList }">
<tr>
<td>${student.id }</td>
<td>${student.name }</td>
<td>${student.age }</td>
<td><a href="${pageContext.request.contextPath}/student/preSave.do?id=${student.id}">修改</a></td>
</tr>
</c:forEach>
</table>

</body>
</html>