springboot(十五)如何引入第三方库

以引用fastjson2为例子

找到官方文档

alibaba.github.io/fastjson2/

pom.xml

<dependency>  
    <groupId>com.alibaba.fastjson2</groupId>  
    <artifactId>fastjson2</artifactId>  
    <version>2.0.52</version>  
</dependency>

将JSON解析为JSONObject

import com.alibaba.fastjson2.JSON;
import com.alibaba.fastjson2.JSONObject;

String text = "{\"name\":\"John\", \"age\":30}";  
JSONObject data = JSON.parseObject(text);  
log.info("data {}",data);

将JSON解析为JSONArray

String textArr = "[\"1\",\"2\",\"3\",\"4\"]";  
JSONArray data2 = JSON.parseArray(textArr);  
log.info("data2 {}",data2);

将JSON解析为Java对象

String text3 = "{\"name\":\"John\", \"age\":30}";  
User data3 = JSON.parseObject(text3, User.class);

将Java对象序列化为JSON

String data4 = JSON.toJSONString(data3);

获取简单属性

String data5 = data3.getName();  
String data6 = String.valueOf(data2.getJSONArray(1));

全部代码

package com.example.fastjson.controller;

import com.alibaba.fastjson2.JSON;
import com.alibaba.fastjson2.JSONArray;
import com.alibaba.fastjson2.JSONObject;
import com.example.fastjson.domain.User;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@RestController
@RequestMapping("test")
@Slf4j
public class TestController {

    @GetMapping("")
    public Map<String, Object> test(){
        String text = "{\"name\":\"John\", \"age\":30}";
        JSONObject data = JSON.parseObject(text);
        log.info("data {}",data);

        String textArr = "[\"1\",\"2\",\"3\",\"4\"]";
        JSONArray data2 = JSON.parseArray(textArr);
        log.info("data2 {}",data2);

        String text3 = "{\"name\":\"John\", \"age\":30}";
        User data3 = JSON.parseObject(text3, User.class);

        String data4 = JSON.toJSONString(data3);

        String data5 = data3.getName();
        String data6 = String.valueOf(data2.getJSONArray(1));

        JSONObject data7 = JSONObject.parseObject("{\"name\":\"John\", \"age\":30}");
        User user = data7.getObject("key", User.class);

        Map<String, Object> result = new HashMap<>();
        result.put("data", data);
        result.put("data2", data2);
        result.put("data3", data3);
        result.put("data4", data4);
        result.put("data5", data5);
        result.put("data6", data6);
        result.put("user", user);
        return result;
    }
}