springboot学习随笔（三）：Controller参数映射

接上章内容，我们看看浏览器参数如何映射到我们的Controller层

我们新建UserController和User实

User.java

package com.example.main;

import java.io.Serializable;

public class User implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = -7359143284242091031L;

    private Long id;
    private String name;
    private Integer age;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

}

UserController.java

package com.example.demo.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.example.main.User;

@RestController
public class UserController {
    
    @RequestMapping("/user")
    public User user(Long id,String name,int age){
        User user = new User();
        user.setId(id);
        user.setName(name);
        user.setAge(18);
        return user;
    }
}

参数映射的方式有三种：

第一种：参数映射

@RestController
public class UserController {
    
    @RequestMapping("/user")
    public User user(Long id,String name,int age){
        User user = new User();
        user.setId(id);
        user.setName(name);
        user.setAge(age);
        return user;
    }
}

在浏览器访问，携带参数

第二种：对象映射

　　

@RequestMapping("/user")
    public User user(User user){
        return user;
    }

在浏览器访问，携带参数

第三种：通过ServletRequest对象

@RequestMapping("/user")
    public User user(ServletRequest request){
        Long id=Long.valueOf(request.getParameter("id"));
        String name =request.getParameter("name");
        int age =Integer.parseInt(request.getParameter("age")) ;
        User user = new User();
        user.setId(id);
        user.setName(name);
        user.setAge(age);
        return user;
    }