private static String receiveFromBackEnd(String url, List<BasicNameValuePair> list) throws IOException, JSONException {
        StringBuilder str = new StringBuilder();

        HttpClient httpclient = new DefaultHttpClient();
        HttpGet httpGet = new HttpGet(url+"?"+ URLEncodedUtils.format(list,"utf-8"));
        httpGet.addHeader(new BasicHeader("Content-Type",
                "application/json"));

        HttpResponse response = httpclient.execute(httpGet);

        BufferedReader reader = new BufferedReader(new InputStreamReader(
                response.getEntity().getContent()));
        String line;
        while ((line = reader.readLine()) != null) {
            str.append(line);
        }

        return str.toString();
    }