Android : Tell me how to send the Json request

I am sending the json request code give the error Is there any way how to send the json request with authentication

//st = json object

        OAuthConsumer consumer = new  DefaultOAuthConsumer("tOzL5hTkSz9KiA2RIAECFL","cj8HLIvzntPmAsffLe5q");
        consumer.setTokenWithSecret(null, null); //i pass token as access token as a null as my server dont need it.

        URL url = new URL("http://api.seatseller.travel/blockTicket");
        HttpURLConnection request = (HttpURLConnection) url.openConnection();

        consumer.sign(request);
        request.connect();

        // send the request
        JSONObject jsonParam = st;
        OutputStreamWriter printout = new OutputStreamWriter(request.getOutputStream());
        printout.write(st.toString());//writeUTF(URLEncoder.encode(jsonParam.toString(),"UTF-8"));
        printout.flush ();
        printout.close ();

        InputStream in = new BufferedInputStream(request.getInputStream());
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        StringBuilder out1 = new StringBuilder();
        String line = "";
        while ((line = reader.readLine()) != null)
        {
            out1.append(line);
        }
      String result= out1.toString() ;