使用GSON将JSON转换为POJO

我正在尝试使用GSON将JSON对象转换为POJO。虽然我没有得到任何错误/异常，但包装器类中的列表对象最终仍然为空。知道我做错了什么吗

JSON字符串

  {
   "location":[
      {
         "id":"1",
         "locationName":"Location 1",
         "eventType":[
            {
               "id":"1",
               "eventName":"Event 1"
            },
            {
               "id":"2",
               "eventName":"Event 2"
            },
            {
               "id":"3",
               "eventName":"Event 3"
            }
         ]
      },
      {
         "id":"2",
         "locationName":"Location 2",
         "eventType":[
            {
               "id":"4",
               "eventName":"Event 4"
            },
            {
               "id":"5",
               "eventName":"Event 5"
            },
            {
               "id":"6",
               "eventName":"Event 6"
            }
         ]
      },
      {
         "id":"3",
         "locationName":"Location 3",
         "eventType":[
            {
               "id":"7",
               "eventName":"Event 7"
            },
            {
               "id":"8",
               "eventName":"Event 8"
            },
            {
               "id":"9",
               "eventName":"Event 9"
            }
         ]
      }
   ]
}

与GSON一起使用的包装器类

public class LocationWrapper {

    public List<Location> locationList;

    public List<Location> getLocationList() {
        return locationList;
    }

    public void setLocationList(List<Location> locationList) {
        this.locationList = locationList;
    }


}

我使用的方法

private void parseGSONfile(String fileName) {


        Gson gson = new Gson();

            //getting string from file, you can insert the above string here
        String json = new JSONParser().getJSONStringFromFile(fileName); 

        List<Location> locationList;
        LocationWrapper locationWrapper = null;


        try {

              locationWrapper = gson.fromJson(json, LocationWrapper.class);

        } catch (Exception e) {
        }

            //here the contained object locationList is still null
        locationList = locationWrapper.getLocationList();
}

private void parseGSONfile（字符串文件名）{
Gson Gson=新的Gson（）；
//从文件中获取字符串，可以在此处插入上面的字符串
String json=new JSONParser（）.getJSONStringFromFile（文件名）；
列表位置列表；
LocationWrapper LocationWrapper=null；
试一试{
locationWrapper=gson.fromJson（json，locationWrapper.class）；
}捕获（例外e）{
}
//此处包含的对象locationList仍然为空
locationList=locationWrapper.getLocationList（）；
}

您的json为字段

location

提供了一个值，但是您的类

LocationWrapper

得到了一个名为

locationList

的字段，因此该字段不匹配。重命名字段或使用

@SerializedName

是的，就是这样，我在列表中的Location类中也有相同的错误。谢谢

public class EventType  {


    private long id;
    private String eventName;

    public EventType() {
    }

    public EventType(long id, String eventName) {
        this.id = id;
        this.eventName = eventName;
    }

    public EventType(int id, String eventName) {
        this.id = id;
        this.eventName = eventName;
    }

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getEventName() {
        return eventName;
    }

    public void setEventName(String eventName) {
        this.eventName = eventName;
    }
}

private void parseGSONfile(String fileName) {


        Gson gson = new Gson();

            //getting string from file, you can insert the above string here
        String json = new JSONParser().getJSONStringFromFile(fileName); 

        List<Location> locationList;
        LocationWrapper locationWrapper = null;


        try {

              locationWrapper = gson.fromJson(json, LocationWrapper.class);

        } catch (Exception e) {
        }

            //here the contained object locationList is still null
        locationList = locationWrapper.getLocationList();
}