对象转化成JSON格式的字符串

public class bbb {
    public static void main(String[] args) throws JsonProcessingException {
        User user = new User();
        user.setAge(22);
        user.setName("小明");
        user.setSex(1);
        List<String> likes = new ArrayList<>();
        likes.add("打球");
        likes.add("洗澡");
        user.setLikes(likes);
        ObjectMapper mapper = new ObjectMapper();
        String res = mapper.writeValueAsString(user);
        // 把对象转化成 json格式 string 
        System.out.println(res);
    }
}

输出：

{“name”:“小明”,“age”:22,“sex”:1,“likes”:[“打球”,“洗澡”]}