fastjson是阿里的一个json转换工具

1. 添加依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.kun</groupId>
    <artifactId>jsonTest</artifactId>
    <version>1.0-SNAPSHOT</version>
    <dependencies>
        <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.75</version>
        </dependency>

    </dependencies>

</project>

2. 新建一个实体类

package com.kun.entity;

public class User {
    private Integer id;
    private String name;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

3. 对象转json

package com.kun.test;

import com.alibaba.fastjson.JSON;
import com.kun.entity.User;

public class Test1 {
    public static void main(String[] args) {
        User user = new User();
        user.setId(1);
        user.setName("小明");
        //将对象转为json
        String userJson = JSON.toJSONString(user);
        System.out.println(userJson);
    }
}

4. json转对象

package com.kun.test;

import com.alibaba.fastjson.JSON;
import com.kun.entity.User;

public class Test2 {
    public static void main(String[] args) {
        String json = "{\"id\":1,\"name\":\"小明\"}";
        User user = JSON.parseObject(json, User.class);
        System.out.println(user);
    }
}