使用平板電腦無法獲得urlConnection.getInputStream（）

Question

我有一個奇怪的情況。使用電話和虛擬設備時，所有請求都能正常工作，但如果我嘗試使用Tablet，則無效。

我的要求：

String path = "https://..."; 
HttpURLConnection urlConnection = null; 
try{ 
    URL url = new URL(path); 
    urlConnection = (HttpURLConnection) url 
      .openConnection(); 
    urlConnection.setRequestMethod("GET"); 
    urlConnection = Tools.setHeader(urlConnection); 
    urlConnection.setDoInput(true); 

    LOG.debug("Start input stream"); 
    InputStream inputStream = urlConnection.getInputStream(); 
    LOG.debug("Input stream exist "+inputStream.toString()); 

    String response = Tools.streamToString(inputStream); 
    inputStream.close(); 
    JSONObject jsonResponse = new JSONObject(response); 

我沒有得到任何錯誤消息。使用代理服務器，我看到我的請求發送和收到的響應。但在程序urlConnection.getInputStream()方法中什麼都沒有。該計劃不會進一步。我沒有看到第二個日誌。

我試圖設置超時，但這沒有幫助。反應很快（1-2秒）。

Answer 1

檢查您的平板電腦的Android版本，可能會導致問題。從ANDROID O開始，它不支持http請求。

解決方法是：下載與棉花糖版本的另一個平板電腦圖像，並檢查它。

更新：試試這個代碼，請

HttpURLConnection connection = null; 
BufferedReader reader = null; 
    try { 
     URL url = new URL(params[0]); 
     connection = (HttpURLConnection)url.openConnection(); 
     connection.connect(); 
     InputStream stream =connection.getInputStream(); 
     reader = new BufferedReader(new InputStreamReader(stream)); 
     StringBuffer buffer = newStringBuffer(); 
      String line = ""; 
      while ((line = reader.readLine()) != null) { 
      buffer.append(line+"\n"); 
      Log.d("Response: ", "> " + line); //here u ll get whole response...... :-) 
     } 
     return buffer.toString(); 
    } 
    catch (MalformedURLException e) { 
     e.printStackTrace(); 
    } 
    catch (IOException e) { 
     e.printStackTrace(); 
    } 
    finally { 
     if (connection != null) { 
      connection.disconnect(); 
     } 
     try { 
      if (reader != null) { 
       reader.close(); 
       } 
      } 
      catch (IOException e) 
     { 
       e.printStackTrace(); 
     } 
    } 
    return null; 
} 

Answer 2

Heyy我兩個手機或平板電腦與我下面的代碼運行。我向你提供我的代碼看看它。

代碼：

public class URLConnectionCheck extends Activity { 

TextView resultText; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_urlconnection_check); 

    resultText = (TextView)findViewById(R.id.resultTextView); 

    new AsynchTaskTest().execute(); 

} 

private class AsynchTaskTest extends AsyncTask<Void,Void,String> 
{ 
    @Override 
    protected String doInBackground(Void... params) { 

     String path = "http://echo.jsontest.com/key/value/one/two"; 

     HttpURLConnection urlConnection = null; 
     BufferedReader reader=null; 

     try{ 
      URL url = new URL(path); 

      urlConnection = (HttpURLConnection)url.openConnection(); 

      urlConnection.connect(); 

      InputStream inputStream = urlConnection.getInputStream(); 
      reader = new BufferedReader(new InputStreamReader(inputStream)); 

      StringBuffer buffer = new StringBuffer(); 
      String line = ""; 

      while((line = reader.readLine()) !=null) { 
       buffer.append(line+"\n"); 

      } 

      return buffer.toString(); 

     } 
     catch (Exception e) 
     { 
      e.printStackTrace(); 
      return "exception"; 
     } 
    } 

    @Override 
    protected void onPostExecute(String aVoid) { 
     super.onPostExecute(aVoid); 

     resultText.setText(aVoid); 
    } 
} 

}

而結果是在我的屏幕爲::