如何将所有这些转换为HTTPS

Question

调试后，我的代码给了我异常“空对象指针引用”，发现响应变量（response = httpClient.execute（httpGet，localContext）;）为空。 我认为，我的错误是使用HTTP客户端。我如何将其转换为HTTPS，因为它是必需的，但是我不确定。

class MyTask extends AsyncTask<String, Void, Void> {

    @Override
    protected Void doInBackground(String ... url) {

        String url2=url[0];
        HttpClient httpClient = new DefaultHttpClient();
        HttpContext localContext = new BasicHttpContext();
        //String url2=url[0];
        HttpGet httpGet = new HttpGet(url2);
        HttpResponse response = null;
        try {
            response = httpClient.execute(httpGet, localContext);
        } catch (IOException e) {
            e.printStackTrace();
        }
        String result = "";

        BufferedReader reader = null;
        try {
            reader = new BufferedReader(
                    new InputStreamReader(
                            response.getEntity().getContent()
                    )
            );
        } catch (IOException e) {
            e.printStackTrace();
        }

        String line = null;
        while (true) {
            try {
                if (!((line = reader.readLine()) != null)) break;
            } catch (IOException e) {
                e.printStackTrace();
            }
            result += line + "\n";
        }
        String FILENAME = "file";


        FileOutputStream fos = null;
        try {
            fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        try {
            fos.write(result.getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        }
        try {
            fos.close();
        } catch (IOException e) {
            e.printStackTrace();
        }


        return null;
    }
}

如果我错了，请告诉我。预先谢谢你