HttpPost参数不起作用

我必须为我的应用程序发出一些客户端-服务器请求。它可以工作，但我不能用PHP读取服务器中发布的参数。没有错误或异常。我尝试了很多不同的方法，但仍然不起作用。

   private class NetworkProvider extends AsyncTask<NetworkingParams, String, String> {
        @Override
        protected String doInBackground(NetworkingParams... networkingParams) {
            String url = networkingParams[0].getUrl();
            String methodName = networkingParams[0].getMethodName();
            JSONObject params = networkingParams[0].getParamJSON();
            InputStream inputStream;
            HttpPost httpPost;
            HttpResponse httpResponse;
            String result = "inputStream is null";
            HttpClient httpClient = new DefaultHttpClient();
            try {
                params.put("method", methodName);
                params.put("uNameDecoded", uNameDecoded);
                params.put("uPassDecoded", uPassDecoded);
            } catch (JSONException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            httpPost = createPostForJSONObject(params, url);
            httpPost.setHeader("Accept", "application/json");
            httpPost.setHeader("Content-type", "application/json");
            try {
                httpResponse = httpClient.execute(httpPost);
                inputStream = httpResponse.getEntity().getContent();
                if (inputStream != null)
                    result = convertInputStreamToString(inputStream);
                return result;
            } catch (ClientProtocolException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        }
        private HttpPost createPostForJSONObject(
                JSONObject params, String url) {
            HttpPost post = new HttpPost(url);
            post.setEntity(createStringEntity(params));
            return post;
        }
        private String convertInputStreamToString(InputStream inputStream) throws IOException{
            BufferedReader bufferedReader = new BufferedReader( new InputStreamReader(inputStream));
            String line = "";
            String result = "";
            while((line = bufferedReader.readLine()) != null)
                result += line;
            inputStream.close();
            return result;
        }
        private HttpEntity createStringEntity(JSONObject params) {
            StringEntity se = null;
            try {
                se = new StringEntity(params.toString());
            } catch (UnsupportedEncodingException e) {
                System.out.println("error creating entity");
            }
            return se;
        }
    }