Android，解析由422響應返回的json的問題

Question

我的web服務器響應422不可處理的實體錯誤，並呈現帶有錯誤列表 的錯誤列表的json響應。

{"name":["has already been taken"]} 

由於某種原因，雖然我的android應用程序拒絕承認，在響應中有任何json。

HttpResponse response = HttpRequest.httpPostJSONObject(this, Urls.getUrlForAccountTeams(this), tm.getJsonObject(), token); 
int code = response.getStatusLine().getStatusCode(); 
if (code == 422){ 
    String responseJson = EntityUtils.toString(response.getEntity()); 
    JSONObject responseEntity = new JSONObject(responseJson); 
    Log.i(TAG, "Created account errors " + responseEntity.toString()); 
} 

從上面的日誌信息下面的輸出是

I/ServiceRefreshData( 780): Server response 422 
I/ServiceRefreshData( 780): Created account errors {} 

如果我使用捲曲張貼完全相同的消息我的Android應用程序來模擬這種派遣我得到的JSON如上圖{"name":["has already been taken"]}這正是我期待在我的Android應用程序中看到的

關於如何獲取json的任何想法。我在與解析全成JSON響應

請求發送JSON沒有問題，使用org.apache.http.HttpResponse的POST請求的結果

public static HttpResponse httpPostJSONObject(Context context, String url, JSONObject data, String token) throws ClientProtocolException, IOException{ 
     HttpClient httpclient = new DefaultHttpClient(); 
     HttpPost httppost = new HttpPost(url); 
     setHeaders(httppost, token); 
     StringEntity se = new StringEntity(data.toString()); 

     httppost.setEntity(se); 
     return httpclient.execute(httppost); 
    } 

UPDATE爲了更清楚我的setHeaders方法看起來像這樣

private static void setHeaders(HttpRequestBase httpget, String token) { 
    httpget.addHeader("Accept", "application/json"); 
    httpget.addHeader("Content-Type", "application/json; charset=UTF-8"); 
    if(token != null){ 
     httpget.addHeader("Authorization", "Token token="+token); 
    } 
} 

爲完整的代碼在我的網絡服務器（Rails的3.2.12），它生產這個JSON是

respond_to do |format| 
    if @team.save 
    format.html { redirect_to @team, notice: 'Team was successfully created.' } 
    format.json { render json: @team, status: :created, location: [:api, @team] } 
    else 
    format.html { render action: "new" } 
    format.json { render json: @team.errors, status: :unprocessable_entity } 
    end 
end 

UPDATE有更多的調試信息按評論 結果改變了我的日誌消息，所以我的方法現在發送的數據看起來像這樣

 try { 
      HttpResponse response = HttpRequest.httpPostJSONObject(this, Urls.getUrlForAccountTeams(this), tm.getJsonObject(), token); 
      int code = response.getStatusLine().getStatusCode(); 
      Log.i(TAG, "Server response " + code); 
      if (code == 422){ 
       String responseJson = EntityUtils.toString(response.getEntity()); 
       JSONObject responseEntity = new JSONObject(responseJson); 
       Log.i(TAG, "Created account errors Response Entity " + responseEntity.toString()); 
       Log.i(TAG, "Created account errors Response " + response.toString()); 
       Log.i(TAG, "Created account errors ResponseJson " + responseJson.toString()); 
      } 
     } catch (ClientProtocolException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } catch (IOException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } catch (JSONException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } 

，併產生

I/ServiceRefreshData( 814): Server response 422 
I/ServiceRefreshData( 814): Created account errors Response Entity {} 
I/ServiceRefreshData( 814): Created account errors Response org.apache.http.message.BasicHttpResponse@44ec4978 
I/ServiceRefreshData( 814): Created account errors ResponseJson {} 

Answer 1

重新啓動我的電腦後，問題就消失了。整個情節我都很困惑。我確信我的代碼是正確的，日誌輸出證明它不是。我只能把它放到一些完全不可思議的緩存問題上。

非常感謝那些幫助過的人。

Answer 2

好我認爲你需要指定一個這樣的標題：

HttpPost httppost = new HttpPost(url); 
httppost.setHeader("Accept", "application/json"); 
httppost.setHeader("Content-type", "application/json");