来源：java 将字符串转为对象，对应到实体类//转成map_murongyuyao的博客-CSDN博客_java 字符串转对象

maven

	<!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
	<dependency>
	    <groupId>com.alibaba</groupId>
	    <artifactId>fastjson</artifactId>
	    <version>1.2.62</version>
	</dependency>

主方法

package test;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

public class test1 {
    public static void main(String[] args){
        String str = "{\"id\":\"1\",\"name\":\"吴彦祖\",\"age\":\"46\"}";
        //将字符串转为json数据
        JSONObject json = JSONObject.parseObject(str);
        System.out.println(json.toJSONString());
        //json数据按key取值
        System.out.println(json.getString("name"));
        System.out.println(json.getString("age"));
        //将json数据转换为java对象/实体类
        UserBean user = JSON.parseObject(str, UserBean.class);
        System.out.println(user.toString());
        //将字符串转成map集合
        Map<String, String> maps = JSON.parseObject(hashMap, HashMap.class);
        System.out.println(maps)
        //将java对象/实体类转换为json数据
        JSONObject jsonUser = (JSONObject) JSONObject.toJSON(user);
        System.out.println("jsonUser："+jsonUser);
    }
}

实体类：

package test;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class UserBean {
    private String name;
    private String id;
    private String age;

}

json合并

import com.alibaba.fastjson.JSONObject;

public class test1 {
    public static void main(String[] args){
        JSONObject json1 = new JSONObject();
        JSONObject json2 = new JSONObject();

        json1.put("name", "吴彦祖");
        json1.put("age", "46");
        System.out.println(json1.toString());

        json2.put("address", "香港");
        json2.put("profession", "演员");
        System.out.println(json2.toString());

        JSONObject jsonMerge = new JSONObject();

        jsonMerge.putAll(json1);
        jsonMerge.putAll(json2);

        System.out.println("合并后："+jsonMerge.toString());

    }
}