2.SpringBoot之返回json数据

2022-07-24 18:36:56

一、创建一个springBoot个项目

操作详情参考：1.SpringBoo之Helloword 快速搭建一个web项目

二、编写实体类

/**

 * Created by CR7 on 2017-8-18 返回Json数据实体类

 */

public class User {

    private int id;

    private String username;

    private String password;

    public String getPassword() {

        return password;

    }

    public void setPassword(String password) {

        this.password = password;

    }

    public String getUsername() {

        return username;

    }

    public void setUsername(String username) {

        this.username = username;

    }

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

}

三、编写控制层Controller类

import com.example.bean.User;

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

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

/**

 * Created by CR7 on 2017-8-18 Json返回数据的Controller

 */

@RestController

@RequestMapping("user")

public class ReturnJsoncontroller {

    @RequestMapping("getUser")

    public User getUser(){

        User user = new User();

        user.setId(1);

        user.setUsername("zhanghaoliang");

        user.setPassword("1231");

        return user;

    }

}

四、测试返回Json数据

浏览器输入http://localhost:8080/user/getUser

得出结果：服务器是以json数据格式返回给浏览器

五、返回list到页面

5.1.返回数据的controller

package com.example.demo;

import com.example.bean.User;

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

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

import java.util.ArrayList;

import java.util.List;

/**

 * Created by CR7 on 2017-8-18 Json返回数据的Controller

 */

@RestController

@RequestMapping("user")

public class ReturnJsoncontroller {

    @RequestMapping("getUserList")

    public List<User> getUserList(){

        User user1  = new User();

        user1.setId(1);

        user1.setUsername("zhanghaoliang");

        user1.setPassword("123");

        User user2 = new User();

        user2.setId(2);

        user2.setUsername("chensi");

        user2.setPassword("456");

        User user3 = new User();

        user3.setId(3);

        user3.setUsername("doudou");

        user3.setPassword("789");

        List<User> list = new ArrayList<>();

        list.add(user1);

        list.add(user2);

        list.add(user3);

        return list;

    }

}

5.2.得出结果

在浏览器访问 http://localhost:8080/user/getUserList

六、返回map到浏览器

既然返回实体，和list的试验过了，那么再试验一下返回Map类型的数据吧

6.1返回的Controller

package com.example.demo;

import com.example.bean.User;

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

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

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

/**

 * Created by CR7 on 2017-8-18 Json返回数据的Controller

 */

@RestController

@RequestMapping("user")

public class ReturnJsoncontroller {

    @RequestMapping("getUserMap")

    public Map<String,User> getUserMap(){

        User user1  = new User();

        user1.setId(1);

        user1.setUsername("zhanghaoliang");

        user1.setPassword("123");

        User user2 = new User();

        user2.setId(2);

        user2.setUsername("chensi");

        user2.setPassword("456");

        User user3 = new User();

        user3.setId(3);

        user3.setUsername("doudou");

        user3.setPassword("789");

        Map<String,User> map = new HashMap<>();

        map.put("user1",user1);

        map.put("user2",user2);

        map.put("user3",user3);

        return map;

    }

}

6.2得出的结果

在浏览器中访问http://localhost:8080/user/getUserMap

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