Android studio post 请求数据

URL url= null;
try {
    url = new URL("http://api.juheapi.com/japi/toh");
    HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

    urlConnection.setRequestMethod("POST");//大写
    urlConnection.setReadTimeout(5000);
    urlConnection.setConnectTimeout(5000);
    urlConnection.setDoOutput(true);

    String param="v=1&month=1&day=24&key=b63fe1f62b3abee4aa1362c3616cd0aa";

    OutputStream outputStream = urlConnection.getOutputStream();
    outputStream.write(param.getBytes());

    if (urlConnection.getResponseCode()==200){
        InputStream inputStream = urlConnection.getInputStream();
        String s = streamToString(inputStream);
        Gson gson=new Gson();
        DateBase base = gson.fromJson(s, DateBase.class);
        List result = base.getResult();

        Message msg=Message.obtain();
        msg.obj=result;
        handler.sendMessage(msg);


    }