GSON이 "BEGIN_OBJECT 예상했는데 BEGIN_ARRAY였나요?"를 던지는 경우

GSON이 "BEGIN_OBJECT 예상했는데 BEGIN_ARRAY였나요?"를 던지는 경우

이것과 같은 JSON 문자열을 해석하려고 합니다.

[
   {
      "updated_at":"2012-03-02 21:06:01",
      "fetched_at":"2012-03-02 21:28:37.728840",
      "description":null,
      "language":null,
      "title":"JOHN",
      "url":"http://rus.JOHN.JOHN/rss.php",
      "icon_url":null,
      "logo_url":null,
      "id":"4f4791da203d0c2d76000035",
      "modified":"2012-03-02 23:28:58.840076"
   },
   {
      "updated_at":"2012-03-02 14:07:44",
      "fetched_at":"2012-03-02 21:28:37.033108",
      "description":null,
      "language":null,
      "title":"PETER",
      "url":"http://PETER.PETER.lv/rss.php",
      "icon_url":null,
      "logo_url":null,
      "id":"4f476f61203d0c2d89000253",
      "modified":"2012-03-02 23:28:57.928001"
   }
]

개체 목록으로 이동합니다.

List<ChannelSearchEnum> lcs = (List<ChannelSearchEnum>) new Gson().fromJson( jstring , ChannelSearchEnum.class);

여기 제가 사용하는 오브젝트 클래스가 있습니다.

import com.google.gson.annotations.SerializedName;

public class ChannelSearchEnum {



@SerializedName("updated_at")
private String updated_at;

@SerializedName("fetched_at")
private String fetched_at;

@SerializedName("description")
private String description;

@SerializedName("language")
private String language;

@SerializedName("title")
private String title;

@SerializedName("url")
private String url;

@SerializedName("icon_url")
private String icon_url;

@SerializedName("logo_url")
private String logo_url;

@SerializedName("id")
private String id;

@SerializedName("modified")
private String modified;

public final String get_Updated_at() {
    return this.updated_at;
}

public final String get_Fetched_at() {
    return this.fetched_at;
}

public final String get_Description() {
    return this.description;
}

public final String get_Language() {
    return this.language;
}

public final String get_Title() {
    return this.title;
}

public final String get_Url() {
    return this.url;
}

public final String get_Icon_url() {
    return this.icon_url;
}

public final String get_Logo_url() {
    return this.logo_url;
}

public final String get_Id() {
    return this.id;
}

public final String get_Modified() {
    return this.modified;
}

        }

하지만 그게 날 미치게 해

com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2

어떻게 고쳐야 할지 생각나는 게 있나요?

문제는 당신이 그 사실을Gson당신은 당신 타입의 물체를 가지고 있어요.넌 아냐.해당 유형의 개체 배열이 있습니다.그렇게 결과를 캐스팅하고 마법처럼 작동하기를 기대할 수는 없습니다.

사용자 가이드:Gson이 대처 방법에 대해 설명합니다.

https://github.com/google/gson/blob/master/UserGuide.md

이 조작은 유효합니다.

ChannelSearchEnum[] enums = gson.fromJson(yourJson, ChannelSearchEnum[].class);

하지만 이것이 더 낫다.

Type collectionType = new TypeToken<Collection<ChannelSearchEnum>>(){}.getType();
Collection<ChannelSearchEnum> enums = gson.fromJson(yourJson, collectionType);

문제는 당신이 타입의 오브젝트를 요구하고 있다는 것입니다.ChannelSearchEnum하지만 당신이 실제로 가지고 있는 것은 타입의 객체입니다.List<ChannelSearchEnum>.

이를 실현하는 방법은 다음과 같습니다.

Type collectionType = new TypeToken<List<ChannelSearchEnum>>(){}.getType();
List<ChannelSearchEnum> lcs = (List<ChannelSearchEnum>) new Gson()
               .fromJson( jstring , collectionType);

JSON 문자열의 경우:

[{"category":"College Affordability",
  "uid":"150151",
  "body":"Ended more than $60 billion in wasteful subsidies for big banks and used the savings to put the cost of college within reach for more families.",
  "url":"http:\/\/www.whitehouse.gov\/economy\/middle-class\/helping middle-class-families-pay-for-college",
  "url_title":"ending subsidies for student loan lenders",
  "type":"Progress",
  "path":"node\/150385"}]

category와 url_title을 recycleview로 출력합니다.

Datum.class

import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;

public class Datum {
@SerializedName("category")
@Expose
private String category;
@SerializedName("uid")
@Expose
private String uid;
@SerializedName("url_title")
@Expose
private String urlTitle;

/**
 * @return The category
 */
public String getCategory() {
    return category;
}

/**
 * @param category The category
 */
public void setCategory(String category) {
    this.category = category;
}

/**
 * @return The uid
 */
public String getUid() {
    return uid;
}

/**
 * @param uid The uid
 */
public void setUid(String uid) {
    this.uid = uid;
}

/**
 * @return The urlTitle
 */
public String getUrlTitle() {
    return urlTitle;
}

/**
 * @param urlTitle The url_title
 */
public void setUrlTitle(String urlTitle) {
    this.urlTitle = urlTitle;
}

}

Request Interface(Request Interface)

import java.util.List;

import retrofit2.Call;
import retrofit2.http.GET;

/**
 * Created by Shweta.Chauhan on 13/07/16.
 */

public interface RequestInterface {

   @GET("facts/json/progress/all")
   Call<List<Datum>> getJSON();
}

데이터 어댑터

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by Shweta.Chauhan on 13/07/16.
 */

public class DataAdapter extends RecyclerView.Adapter<DataAdapter.MyViewHolder>{

private Context context;
private List<Datum> dataList;

public DataAdapter(Context context, List<Datum> dataList) {
    this.context = context;
    this.dataList = dataList;
}

@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.data,parent,false);
    return new MyViewHolder(view);
}

@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
    holder.categoryTV.setText(dataList.get(position).getCategory());
    holder.urltitleTV.setText(dataList.get(position).getUrlTitle());

}

@Override
public int getItemCount() {
    return dataList.size();
}

public class MyViewHolder extends RecyclerView.ViewHolder{

    public TextView categoryTV, urltitleTV;

    public MyViewHolder(View itemView) {
        super(itemView);
        categoryTV = (TextView) itemView.findViewById(R.id.txt_category);
        urltitleTV = (TextView)     itemView.findViewById(R.id.txt_urltitle);
    }
}
}

그리고 마지막으로 MainActivity.java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

public class MainActivity extends AppCompatActivity {

private RecyclerView recyclerView;
private DataAdapter dataAdapter;
private List<Datum> dataArrayList;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    initViews();
}

private void initViews(){
    recyclerView=(RecyclerView) findViewById(R.id.recycler_view);
    recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
    loadJSON();
}

private void loadJSON(){
    dataArrayList = new ArrayList<>();
    Retrofit retrofit=new Retrofit.Builder().baseUrl("https://www.whitehouse.gov/").addConverterFactory(GsonConverterFactory.create()).build();
    RequestInterface requestInterface=retrofit.create(RequestInterface.class);
    Call<List<Datum>> call= requestInterface.getJSON();
    call.enqueue(new Callback<List<Datum>>() {
        @Override
        public void onResponse(Call<List<Datum>> call, Response<List<Datum>> response) {
            dataArrayList = response.body();
            dataAdapter=new DataAdapter(getApplicationContext(),dataArrayList);
            recyclerView.setAdapter(dataAdapter);
        }

        @Override
        public void onFailure(Call<List<Datum>> call, Throwable t) {
            Log.e("Error",t.getMessage());
        }
    });
}
}

다른 방법으로는

당신의 반응을 다음과 같이 보이게 하기 위해

myCustom_JSON Response

{"master":[
   {
      "updated_at":"2012-03-02 21:06:01",
      "fetched_at":"2012-03-02 21:28:37.728840",
      "description":null,
      "language":null,
      "title":"JOHN",
      "url":"http://rus.JOHN.JOHN/rss.php",
      "icon_url":null,
      "logo_url":null,
      "id":"4f4791da203d0c2d76000035",
      "modified":"2012-03-02 23:28:58.840076"
   },
   {
      "updated_at":"2012-03-02 14:07:44",
      "fetched_at":"2012-03-02 21:28:37.033108",
      "description":null,
      "language":null,
      "title":"PETER",
      "url":"http://PETER.PETER.lv/rss.php",
      "icon_url":null,
      "logo_url":null,
      "id":"4f476f61203d0c2d89000253",
      "modified":"2012-03-02 23:28:57.928001"
   }
]
}

대신

서버_JSONRESPonse

[
   {
      "updated_at":"2012-03-02 21:06:01",
      "fetched_at":"2012-03-02 21:28:37.728840",
      "description":null,
      "language":null,
      "title":"JOHN",
      "url":"http://rus.JOHN.JOHN/rss.php",
      "icon_url":null,
      "logo_url":null,
      "id":"4f4791da203d0c2d76000035",
      "modified":"2012-03-02 23:28:58.840076"
   },
   {
      "updated_at":"2012-03-02 14:07:44",
      "fetched_at":"2012-03-02 21:28:37.033108",
      "description":null,
      "language":null,
      "title":"PETER",
      "url":"http://PETER.PETER.lv/rss.php",
      "icon_url":null,
      "logo_url":null,
      "id":"4f476f61203d0c2d89000253",
      "modified":"2012-03-02 23:28:57.928001"
   }
]

코드

  String server_JSONResponse =.... // the string in which you are getting your JSON Response after hitting URL
String myCustom_JSONResponse="";// in which we will keep our response after adding object element to it
     MyClass apiResponse = new MyClass();

     myCustom_JSONResponse="{\"master\":"+server_JSONResponse+"}";



    apiResponse = gson.fromJson(myCustom_JSONResponse, MyClass .class);

이제부터는 다른 것과 다를 바 없다.GSON Parsing

GSON 사용자 가이드에 따르면 할 수 없습니다.

수집 제한

임의 개체의 컬렉션을 직렬화할 수 있지만 이 컬렉션에서 직렬화를 취소할 수는 없습니다.사용자가 결과 객체의 유형을 지정할 수 없기 때문입니다.

이것은 Json 배열 목록처럼 보입니다.따라서 사용하는 것이 가장 좋습니다.ArrayList데이터를 처리할 수 있습니다.api 엔드 포인트에 다음과 같이 어레이 목록을 추가합니다.

 @GET("places/")
Call<ArrayList<Place>> getNearbyPlaces(@Query("latitude") String latitude, @Query("longitude") String longitude);

코틀린:

var list=ArrayList<Your class name>()
val listresult: Array<YOUR CLASS NAME> = Gson().fromJson(
                YOUR JSON RESPONSE IN STRING,
                Array<Your class name>:: class.java)

list.addAll(listresult)

Gson에게 아래와 같이 추가 응답 유형을 알려야 합니다.

import com.google.common.reflect.TypeToken;
import java.lang.reflect.Type;


Type collectionType = new TypeToken<List<UserSite>>(){}.getType();
List<UserSite> userSites  = gson.fromJson( response.getBody() , collectionType);

이것이 GSON을 사용하는 가장 좋은 방법인지는 모르겠지만, 나에게는 효과가 있습니다.이런 거 쓰면 돼요MainActivity:

 public void readJson() {
    dataArrayList = new ArrayList<>();
    String json = "[\n" + IOHelper.getData(this) + "\n]\n";
    Log.d(TAG, json);
    try{
        JSONArray channelSearchEnums = new JSONArray(json);

        for(int i=0; i< channelSearchEnums.length(); i++)
        {
            JSONObject enum = channelSearchEnums.getJSONObject(i);
            ChannelSearchEnum channel = new ChannelSearchEnum(
                   enum.getString("updated_at"), enum.getString("fetched_at"),
                   enum.getString("description"), enum.getString("language"),
                   enum.getString("title"), enum.getString("url"),
                   enum.getString("icon_url"), enum.getString("logo_url"),
                   enum.getString("id"), enum.getString("modified"))         

                   dataArrayList.add(channel);
        }

         //The code and place you want to show your data            

    }catch (Exception e)
    {
        Log.d(TAG, e.getLocalizedMessage());
    }
}

현밖에 없지만 더블이나 int를 원한다면getDouble또는getInt너무.

의 방법IOHelperclass가 다음입니다(여기서 경로는 내부 스토리지에 저장됩니다).

 public static String getData(Context context) {
    try {
        File f = new File(context.getFilesDir().getPath() + "/" + fileName);
        //check whether file exists
        FileInputStream is = new FileInputStream(f);
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        return new String(buffer);
    } catch (IOException e) {
        Log.e("TAG", "Error in Reading: " + e.getLocalizedMessage());
        return null;
    }
}

자세한 것은, 이 비디오를 봐 주세요.이 비디오에서는, 다음의 코드를 입수할 수 있습니다.readJson(); 그리고 이 스레드는 내가 코드를 얻을 수 있습니다.getData().

public ChannelSearchEnum[] getChannelSearchEnum(Response response) {
        return response.as(ChannelSearchEnum[].class, ObjectMapperType.GSON);
}

위는 문제를 해결하고 응답을 전달하면 클래스의 매핑된 개체 배열이 반환됩니다.

솔루션

1. 저는 발리 도서관을 이용하고 있습니다.GSON을 사용하여 발리에서 응답을 자동으로 구문 분석합니다.

    [
            {
                "name": "Naruto: Shippuuden",
                "description": "It has been two and a half years since Naruto Uzumaki left Konohagakure, the Hidden Leaf Village, for intense training following events which fueled his desire to be stronger. Now Akatsuki, the mysterious organization of elite rogue ninja, is closing in on their grand plan which may threaten the safety of the entire shinobi world.",
                "Rating": "8.16",
                "episode": 500,
                "categorie":"Animation | Drama | Adventure",
                "studio":"Studio Pierrot",
                "img": "https://myanimelist.cdn-dena.com/images/anime/5/17407.jpg"
            },
            {
                "name": "One Piece",
                "description": "Gol D. Roger was known as the 'Pirate King',the strongest and most infamous being to have sailed the Grand Line. The capture and death of Roger by the World Government brought a change throughout the world. His last words before his death revealed the existence of the greatest treasure in the world, One Piece. It was this revelation that brought about the Grand Age of Pirates, men who dreamed of finding One Piece—which promises an unlimited amount of riches and fame—and quite possibly the pinnacle of glory and the title of the Pirate King.",
                "Rating": "8.54",
                "episode": 700,
                 "categorie":"Animation | Drama | Adventure",
                "studio":"Toei Animation",
                "img": "https://myanimelist.cdn-dena.com/images/anime/6/73245.jpg"
            }
        ]

2. 이것은 나의 모델이다.

    public class DataResponse implements Serializable {
    
        @SerializedName("studio")
        private String studio;
    
        @SerializedName("img")
        private String img;
    
        @SerializedName("categorie")
        private String categorie;
    
        @SerializedName("Rating")
        private String rating;
    
        @SerializedName("name")
        private String name;
    
        @SerializedName("description")
        private String description;
    
        @SerializedName("episode")
        private int episode;
    
        public void setStudio(String studio){
            this.studio = studio;
        }
    
        public String getStudio(){
            return studio;
        }
    
        public void setImg(String img){
            this.img = img;
        }
    
        public String getImg(){
            return img;
        }
    
        public void setCategorie(String categorie){
            this.categorie = categorie;
        }
    
        public String getCategorie(){
            return categorie;
        }
    
        public void setRating(String rating){
            this.rating = rating;
        }
    
        public String getRating(){
            return rating;
        }
    
        public void setName(String name){
            this.name = name;
        }
    
        public String getName(){
            return name;
        }
    
        public void setDescription(String description){
            this.description = description;
        }
    
        public String getDescription(){
            return description;
        }
    
        public void setEpisode(int episode){
            this.episode = episode;
        }
    
        public int getEpisode(){
            return episode;
        }
    
        @Override
        public String toString(){
            return 
                "Response{" + 
                "studio = '" + studio + '\'' + 
                ",img = '" + img + '\'' + 
                ",categorie = '" + categorie + '\'' + 
                ",rating = '" + rating + '\'' + 
                ",name = '" + name + '\'' + 
                ",description = '" + description + '\'' + 
                ",episode = '" + episode + '\'' + 
                "}";
            }
    }

3. my api 메서드

define globle

private List<DataResponse> dataResponses = new ArrayList<>();

    private void volleyAutomation(String url) {
            JSONArray array = new JSONArray();
            JsonArrayRequest request_json = new JsonArrayRequest(Request.Method.GET, url, array,
                    new Response.Listener<JSONArray>() {
                        @Override
                        public void onResponse(JSONArray response) {
    
                            GsonBuilder gsonBuilder = new GsonBuilder();
                            Gson gson = gsonBuilder.create();
                           dataResponses = Arrays.asList(gson.fromJson(response.toString(), DataResponse[].class));
    
                            rvList(dataResponses);
                            Log.d("respknce___", String.valueOf(dataResponses.size()));
                        }
                    }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError volleyError) {
    
                }
            });
            RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
            requestQueue.add(request_json);
        }

언급URL : https://stackoverflow.com/questions/9598707/gson-throwing-expected-begin-object-but-was-begin-array