SpringMVC模型数据-优快云博客

本文链接：https://blog.youkuaiyun.com/weixin_57667101/article/details/128386804

SpringMVC 模型数据

引入：开发中, 控制器/处理器中获取的数据如何放入 request / session域，然后在前端(VUE/JSP/…)取出显示

前期代码准备

entity

public class Master {
    private String name;
    private String address;
    private Pet pet;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public Pet getPet() {
        return pet;
    }

    public void setPet(Pet pet) {
        this.pet = pet;
    }

    public Master() {
    }

    public Master(String name, String address, Pet pet) {
        this.name = name;
        this.address = address;
        this.pet = pet;
    }

    @Override
    public String toString() {
        return "Master{" +
                "name='" + name + '\'' +
                ", address='" + address + '\'' +
                ", pet=" + pet +
                '}';
    }
}

填写数据的页面

<%--
  Created by IntelliJ IDEA.
  User: PigBrother
  Date: 2022/11/8
  Time: 22:47
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>测试模型数据</title>
</head>
<body>
<h1>添加主人信息</h1>
<!--
老韩解读
1. 这里的字段名称和对象的属性名保持一致,级联添加属性也是一样保持名字对应关系
2. 如果只是添加主人信息，则去掉宠物号和宠物名输入框即可,pet 为null-->
<form action="vote/vote08" method="post">
    主人地址:<input type="text" name="address"><br>
    主人名:<input type="text" name="name"><br>
    宠物号:<input type="text" name="pet.id"><br>
    宠物名:<input type="text" name="pet.name"><br>
    <input type="submit" value="添加主人和宠物">
</form>

<form action="vote/fillString" method="post">
    color:<input type="text" name="color"><br>
    <input type="submit" value="提交">
</form>



<br/><hr/>
<h1>添加主人信息[测试session]</h1>
<form action="vote/vote08" method="post">
    主人号:<input type="text" name="id"><br>
    主人名:<input type="text" name="name"><br>
    宠物号:<input type="text" name="pet.id"><br>
    宠物名:<input type="text" name="pet.name"><br>
    <input type="submit" value="添加主人和宠物">
</form>
</body>
</html>

数据展示页面

<%--
  Created by IntelliJ IDEA.
  User: PigBrother
  Date: 2022/11/8
  Time: 16:49
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>vote_ok </title>
</head>
<body>
<h1>获取的的数据显示页面</h1>
<hr>
取出request 域的数据
<br>
hobby: ${hobby }<br>
address: ${address }<br>
主人名字= ${requestScope.master.name }
主人名字= ${requestScope.master.address }
主人信息= ${requestScope.master }
宠物名字= ${requestScope.master.pet.name }
fillParam = ${requestScope.color}


<hr>
取出session 域的数据<br>
主人名字= ${sessionScope.master2.name }
主人信息= ${sessionScope.master2 }
</body>
</html>

放入request 域

方式一：通过 HttpServletRequest 放入 request 域

@RequestMapping(value = "/vote05")
public String test05(Master master, HttpServletRequest request,
                     HttpServletResponse response) {

    request.setAttribute("hobby", "lanqiu");
    request.setAttribute("address", "CHINA");
    System.out.println(master);

    return "vote_ok";
}

方式二：通过请求的方法参数 Map<String,Object> 放入 request 域

@RequestMapping(value = "/vote06")
    public String test06(Map<String, Object> map, Master master) {

        System.out.println("=====test06()=====~");
        //老韩解读
        //1. springMVC 会将map 的k-v 放入到request 域对象
//        map.put("master", master);
        map.put("address", "beijing");
        //返回到一个结果
        return "vote_ok";
    }

通过返回 ModelAndView 对象实现 request 域数据

//通过返回ModelAndView 对象实现request 域数据
@RequestMapping(value = "/vote07")
public ModelAndView test07(Master master) {

    System.out.println("=====test07()=====~");
    //创建一个ModelAndView 对象
    ModelAndView modelAndView = new ModelAndView();
    //下面这句话就等价于将master 对象放入到request 域中，属性名“master”
    modelAndView.addObject("master", master);
    modelAndView.addObject("address", "shanghai");
    modelAndView.setViewName("vote_ok");

    //返回到一个结果
    return modelAndView;
}

将数据放入session 域中

@RequestMapping(value = "/vote08")
public String test08(Map<String, Object> map, Master master,
                     HttpSession session) {
    System.out.println("======test08()======");
    map.put("address", "guangzhou");
    //在session 域也放入master 对象
    session.setAttribute("master2", master);
    return "vote_ok";
}