public void postRequest(View view) {

        new Thread(new Runnable() {
            @Override
            public void run() {
                OutputStream outputStream = null;
                InputStream inputStream = null;
                try {
                    URL url = new URL(BASE_URL+"/post/comment");
                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                    connection.setRequestMethod("POST");
                    connection.setConnectTimeout(10000);
                    connection.setRequestProperty("Content-Type","application/json;charset=UTF-8");
                    CommandItem commandItem = new CommandItem("2341","mark...");
                    Gson gson = new Gson();
                    String json = gson.toJson(commandItem);
                    byte[] bytes = json.getBytes("UTF-8");
                    Log.e(TAG, "run: "+bytes.length );
                    connection.setRequestProperty("Content-Length",String.valueOf(bytes.length));
                    //连接
                    connection.connect();
                    //数据给出去
                    outputStream = connection.getOutputStream();

                    outputStream.write(bytes);
                    outputStream.flush();
                    //拿到结果
                    int responseCode = connection.getResponseCode();
                    Log.e(TAG, "run: "+responseCode );
                    if (responseCode == 200){

                        inputStream = connection.getInputStream();
                        BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));
                        String line = br.readLine();
                        Log.e(TAG, "run: "+line );
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }finally {
                    if (outputStream!=null) {
                        try {
                            outputStream.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                    if (inputStream!=null) {
                        try {
                            inputStream.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }).start();
    }