fastjson学习

1、添加依赖：

<!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.46</version>
</dependency>

2、fastJson相互之间转换：

User类

1 import lombok.Data;
2 
3 @Data
4 public class User {
5 
6     private Long   id;
7     private String name;
8 }

Group类：

 1 import lombok.Data;
 2 import lombok.NoArgsConstructor;
 3 import java.util.ArrayList;
 4 import java.util.List;
 5 
 6 @Data
 7 @NoArgsConstructor
 8 public class Group {
 9 
10     private Long       id;
11     private String     name;
12     private List<User> users = new ArrayList<User>();
13 
14 }

字符串转JSON对象

1     /**
2      * 字符串转JSON对象
3      */
4   public static JSONObject jsonStrToObject(String str){
5         JSONObject jsonObj = JSON.parseObject(str);
6         System.out.println(jsonObj.get("id"));
7         System.out.println(jsonObj.get("name"));
8         return jsonObj;
9     }

字符串转POJO对象

1 /**
2      * 字符串转POJO对象
3      */
4     public  static  User jsonStrToPOJO(String str){
5         User user = JSON.parseObject(str,User.class);
6         System.out.println(user.getName());
7         return user; 
8 }

POJO对象转字符串

 1     /**
 2      * POJO对象转字符串
 3      */
 4     public static String PojoToStr(){
 5 
 6         Group group = new Group();
 7         group.setId(0L);
 8         group.setName("admin");
 9 
10         User guestUser = new User();
11         guestUser.setId(2L);
12         guestUser.setName("guest");
13 
14         User rootUser = new User();
15         rootUser.setId(3L);
16         rootUser.setName("root");
17 
18         List<User> list = new ArrayList<>();
19         list.add(guestUser);
20         list.add(rootUser);
21 
22         group.setUsers(list);
23 
24         String jsonString = JSON.toJSONString(group);
25         return jsonString;
26     }

方法调用：

1     public static void main(String[] args) {
2 
3         String str = "{\"id\":2,\"name\":\"guest\"}";
4         jsonStrToObject(str);
5         jsonStrToPOJO(str);
6         PojoToStr();
7 
8     }

示例代码：github

参考：https://github.com/alibaba/fastjson/wiki/JSON_API_cn