Android中的outputStream写入方法

Question

我正在为一家与MySQL数据库通信的公司构建应用程序，试图将新条目发送到服务器，但是无法使用outputstream write方法工作，我知道有一个错误，但是我似乎找不到解决方法

这是我的代码：

OutputStreamWriter outputStreamWriter = new OutputStreamWriter(new OutputStream() {
                @Override
                public void write(int b) throws IOException {

                    Log.e("Car DetailStream Writer","outputStreamWriter write method called");

                    try {
                        int isLargeAsInt = car.isLarge() ? 1 : 0;
                        int isDieselAsInt = car.isDiesel() ? 1 : 0;
                        Log.e("Car Details Write Data",car.getCarModel());
                        writeData =
                                URLEncoder.encode("carModel", "UTF-8") + "=" + URLEncoder.encode(car.getCarModel(), "UTF-8") + "&" +
                                        URLEncoder.encode("carYear", "UTF-8") + "=" + URLEncoder.encode(car.getYear(), "UTF-8") + "&" +
                                        URLEncoder.encode("carPlate", "UTF-8") + "=" + URLEncoder.encode(car.getPlateNumber(), "UTF-8") + "&" +
                                        URLEncoder.encode("isLarge", "UTF-8") + "=" + isLargeAsInt + "&" +
                                        URLEncoder.encode("isDiesel", "UTF-8") + "=" + isDieselAsInt + "&" +
                                        URLEncoder.encode("currentMileage", "UTF-8") + "=" + car.getCurrentMileage();
                        Log.e("Written Data", writeData);
                    } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }

                }
            });
            BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter);
            Log.d("Buffered Writer","Buffered Writer Created");


bufferedWriter.write(writeData);
                bufferedWriter.flush();

这是错误：

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.String.length()' on a null object reference
    at java.io.Writer.write(Writer.java:157)
    at com.example.trknil.turknilmanagement.utils.SendUtils.makeHttpRequest(SendUtils.java:124)

这是第124行：

bufferedWriter.write(writeData);

任何人都可以修复该代码，并告诉我我哪里出错了。