Android Studio HttpURLConnection不发布数据

Question

我想通过使用AsyncTask将数据发布到我的localhost，可以通过Genymotion的10.0.3.2:8787和Localhost的127.0.0.1:8787访问。但是，它似乎没有发布任何内容。以下是我的代码;

private class LocationUpdateTask extends AsyncTask<String, Void, Void> { 
    @Override 
    protected Void doInBackground(String... params) { 
     String _url = "http://10.0.3.2:8787/user_locations/save"; 
     HttpURLConnection httpClient = null; 
     try { 
      for (int i = 0; i < params.length; i++) { 
       String urlParameters = params[i]; 
       System.out.println(urlParameters); // Prints fine here. 
       URL url = new URL(_url); 
       httpClient = (HttpURLConnection) url.openConnection(); 
       httpClient.setRequestMethod("POST"); 
       httpClient.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
       httpClient.setRequestProperty("Content-Language", "en-US"); 
       httpClient.setUseCaches(false); 
       httpClient.setDoInput(true); 
       httpClient.setDoOutput(true); 
       //Send request 
       DataOutputStream wr = new DataOutputStream(httpClient.getOutputStream()); 
       wr.writeBytes(urlParameters); 
       wr.flush(); 
       wr.close(); 
      } 
     } 
     catch (Exception e) { 
      e.printStackTrace(); 
     } 
     finally { 
      if (httpClient != null) { 
       httpClient.disconnect(); 
      } 
     } 

     return null; 
    } 
} 

public class LocationUpdaterListener implements LocationListener 
{ 
    @Override 
    public void onLocationChanged(Location location) { 
     //String text = "Lat: " + location.getLatitude() + "\nLong: " + location.getLongitude(); 
     //Toast.makeText(getApplicationContext(), text, Toast.LENGTH_LONG).show(); 
     HashMap<String, String> postDataParams=new HashMap<String, String>(); 
     postDataParams.put("fuid", profileId); 
     postDataParams.put("lat", String.valueOf(location.getLatitude())); 
     postDataParams.put("lng", String.valueOf(location.getLongitude())); 
     postDataParams.put("alt", String.valueOf(location.getAltitude())); 
     postDataParams.put("br", String.valueOf(location.getBearing())); 
     postDataParams.put("acc", String.valueOf(location.getAccuracy())); 

     String urlParameters = null; 

     try { 
      urlParameters = "fuid=" + URLEncoder.encode(postDataParams.get("fuid"), "UTF-8")+ 
        "&lat="+URLEncoder.encode(postDataParams.get("lat"), "UTF-8")+ 
        "&lng="+URLEncoder.encode(postDataParams.get("lng"), "UTF-8")+ 
        "&alt="+URLEncoder.encode(postDataParams.get("alt"), "UTF-8")+ 
        "&br="+URLEncoder.encode(postDataParams.get("br"), "UTF-8")+ 
        "&acc="+URLEncoder.encode(postDataParams.get("acc"), "UTF-8"); 
     } 
     catch (Exception e) { 
      e.printStackTrace(); 
     } 
     finally { 
      if (urlParameters != null){ 
       new LocationUpdateTask().execute(urlParameters); 
      } 
     } 
    } 

    @Override 
    public void onProviderDisabled(String provider) { } 

    @Override 
    public void onProviderEnabled(String provider) { } 

    @Override 
    public void onStatusChanged(String provider, int status, Bundle extras) { } 
} 

没有任何异常抛出。如果我通常通过浏览器访问并传递参数，它工作得很好。所以，我认为我的代码一定是错的。

那么，这是错误的我的代码？或者我应该尝试看看为什么这不起作用？

任何建议表示赞赏。

Answer 1

我终于搞定了。我不知道为什么，但看起来我不得不让HttpURLConnection在最后的代码处调用getInputStream，比如;

InputStream is = httpClient.getInputStream(); 

或

// getResponseCode also calls getInputStream. 
int responseCode = httpClient.getResponseCode(); 

所以，最后我的代码看起来像这样，

private class LocationUpdateTask extends AsyncTask<String, Void, Void> { 
    @Override 
    protected Void doInBackground(String... params) { 
     String _url = "http://10.0.3.2:8787/user_locations/save"; 
     HttpURLConnection httpClient = null; 
     try { 
      for (int i = 0; i < params.length; i++) { 
       String urlParameters = params[i]; 
       URL url = new URL(_url); 
       httpClient = (HttpURLConnection) url.openConnection(); 
       httpClient.setRequestMethod("POST"); 
       httpClient.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
       httpClient.setRequestProperty("Content-Language", "en-US"); 
       httpClient.setUseCaches(false); 
       httpClient.setDoInput(true); 
       httpClient.setDoOutput(true); 
       //Send request 
       DataOutputStream wr = new DataOutputStream(httpClient.getOutputStream()); 
       wr.writeBytes(urlParameters); 
       wr.flush(); 
       wr.close(); 
       //InputStream is = httpClient.getInputStream(); 
       int responseCode = httpClient.getResponseCode(); 
      } 
     } 
     catch (Exception e) { 
      //Log.e("TAG", "Exception", e.fillInStackTrace()); 
      e.printStackTrace(); 
     } 
     finally { 
      if (httpClient != null) { 
       httpClient.disconnect(); 
      } 
     } 
     return null; 
    } 
}