java - 如何使用 Jackson ObjectMapper 解析 java 对象的 json 响应

Question

这是我的 Json 响应

"postedevent": [
    {
        "status": "true",
        "event_id": "800",
        "num_of_image_event": "0",
        "title": "Testy",
        "photo": "http://54.200.110.49/checkplanner/img/upload/21310059819profile_image_1409303464798.png",
        "event_date": "2014-08-29",
        "fullDate": "Friday - August 29, 2014",
        "event_from": "12:00AM",
        "event_to": "12:15AM",
        "city": "Ahm",
        "state": "CA",
        "member_id": "471",
        "username": "Krishna Mohan",
        "pencil": "yes",
        "attend": "yes",
        "company": "Development"
    }
 ]

这是从 json 响应获取 java 对象的 java 类

public class PostedEvent {

String status;
int event_id;
int num_of_image_event;
String title;
String photo;
String event_date;
String fullDate;
String event_from;
String event_to;
String city;
String state;
String member_id;
String username;
String pencil;
String attend;
String company;


}


public class PostedEvnetsList 
{
     ArrayList<PostedEvent> postedevent;
}

我是这样解析的

InputStream is = WebResponse.getResponse(url);
ObjectMapper mapper = new ObjectMapper();
PostedEvnetsList mList = null;
mList = mapper.readValue(is,PostedEvnetsList.class);
eventList = mList.postedevent;

我收到以下解析异常

jackson.map.exc.UnrecognizedPropertyException:无法识别的字段“status”(com.example.jsonproforexam.PostedEvent 类)，未标记为可忽略

我已经声明了与 json 响应中相同的字段，那么为什么我会收到此异常 请帮忙

Answer 1

您的 PostedEvent 字段和 PostedEventsList 的 PostedEvent 字段不可访问。

您必须将它们设置为 public (不推荐)或为它们提供 POJO 风格的公共(public) getter 和 setter。

然后 Jackson 将能够反序列化，错误就会消失。