How to encode data in URL and upload file on same connection?

Question

I want to upload file to server from the device and send some data as well on the same request by encoding in the url, i have tried but it is not working. What i am doing wrong and How can we do it?

HttpURLConnection conn = null;
DataOutputStream dos = null;
DataInputStream inStream = null;
String existingFileName = Environment.getExternalStorageDirectory().getAbsolutePath() + "/recorded_audio.3gp";
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
int bytesRead, bytesAvailable, bufferSize;
byte[] buffer;
int maxBufferSize = 1 * 1024 * 1024;
String responseFromServer = "";
String urlString = "http://mywebsite.com/uploadAudio.php";

@Override
protected String doInBackground(String... params) {
    String uploading_file = params[0];

    try{
        //------------------ CLIENT REQUEST
        FileInputStream fileInputStream = new FileInputStream(new File(uploading_file));
        // open a URL connection to the Servlet
        URL url = new URL(urlString);
        // Open a HTTP connection to the URL
        conn = (HttpURLConnection) url.openConnection();
        // Allow Inputs
        conn.setDoInput(true);
        // Allow Outputs
        conn.setDoOutput(true);
        // Don't use a cached copy.
        conn.setUseCaches(false);
        // Use a post method.
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Connection", "Keep-Alive");
        conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);

        // Sending necessary Data(userID, tags, location)
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("id", ("my_data"));
        JSONObject data = new JSONObject();
        data.put("user_data", jsonObject);
        String jsonStr = data.toString();

        dos = new DataOutputStream(conn.getOutputStream());
        String post_data = URLEncoder.encode("user", "UTF-8") + "=" + URLEncoder.encode(jsonStr, "UTF-8");
        dos.writeBytes(post_data);
        dos.writeBytes(twoHyphens + boundary + lineEnd);
        dos.writeBytes("Content-Disposition: form-data; name=\"uploadedfile\";filename=\"" + uploading_file + "\"" + lineEnd);
        dos.writeBytes(lineEnd);

        // create a buffer of maximum size
        bytesAvailable = fileInputStream.available();
        bufferSize = Math.min(bytesAvailable, maxBufferSize);
        buffer = new byte[bufferSize];
        // read file and write it into form...
        bytesRead = fileInputStream.read(buffer, 0, bufferSize);

        while (bytesRead > 0) {

            dos.write(buffer, 0, bufferSize);
            bytesAvailable = fileInputStream.available();
            bufferSize = Math.min(bytesAvailable, maxBufferSize);
            bytesRead = fileInputStream.read(buffer, 0, bufferSize);

        }

        // send multipart form data necessary after file data...
        dos.writeBytes(lineEnd);
        dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
        // close streams
        Log.e("Debug", "File is written");
        fileInputStream.close();
        dos.flush();
        dos.close();

    }catch(MalformedURLException ex){
        Log.e("Debug", "error: " + ex.getMessage(), ex);
    } catch(IOException ioe){
        Log.e("Debug", "error: " + ioe.getMessage(), ioe);
    } catch (JSONException e) {
        e.printStackTrace();
    }
    InputStream inputStream = null;
    String line = "";
    try

    {
        inputStream = conn.getInputStream();
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"));
        if ((line = bufferedReader.readLine()) != null) {
            Log.e("Debug", "Server Response " + line);
        }
        bufferedReader.close();
        inputStream.close();
        conn.disconnect();
    } catch(
            IOException e)

    {
        e.printStackTrace();
    }
    return line;
    }
}

    UploadAudio uploadAudio = new UploadAudio();
    uploadAudio.execute(existingFileName);

This code i have written for uploading file and POST data through URL. I have also created a php file for server.