本文为android开发网络编程系列内容，权限的配置以及接口文档和后台程序，请移架到课程详情！

android网络编程

接口

代码

 public void downFile(View view) {
        new Thread(new Runnable() {
            @Override
            public void run() {
                InputStream inputStream = null;
                FileOutputStream fileOutputStream = null;
                try {
                    URL url = new URL(BASE_URL + "/download/11");
                    HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
                    httpURLConnection.setConnectTimeout(10000);
                    httpURLConnection.setRequestMethod("GET");
                    httpURLConnection.setRequestProperty("Accept-Language","zh-CN,zh;q=0.9");
                    httpURLConnection.setRequestProperty("Accept","*/*");
                    httpURLConnection.connect();
                    int responseCode = httpURLConnection.getResponseCode();
                    Log.d(TAG,"responseCode == > " + responseCode);
                    if(responseCode == HttpURLConnection.HTTP_OK) {
                        String headerField = httpURLConnection.getHeaderField("Content-disposition");
                        Log.d(TAG,"headerField == > " + headerField);
                        //                        int index = headerField.indexOf("filename=");
                        //                        String fileName = headerField.substring(index + "filename=".length());
                        //                        Log.d(TAG,"fileName -- > " + fileName);
                        String fileName = headerField.replace("attachment; filename=","");
                        Log.d(TAG,"fileName -- > " + fileName);
                        File picFile = RequestTestActivity.this.getExternalFilesDir(Environment.DIRECTORY_PICTURES);
                        if(!picFile.exists()) {
                            picFile.mkdirs();
                        }
                        File file = new File(picFile + File.separator + fileName);
                        if(!file.exists()) {
                            file.createNewFile();
                        }
                        fileOutputStream = new FileOutputStream(file);
                        inputStream = httpURLConnection.getInputStream();
                        byte[] buffer = new byte[1024];
                        int len;
                        while((len = inputStream.read(buffer,0,buffer.length)) != -1) {
                            fileOutputStream.write(buffer,0,len);
                        }
                        fileOutputStream.flush();
                    }
                } catch(Exception e) {
                    e.printStackTrace();
                } finally {
                    IOUtils.ioClose(inputStream);
                    IOUtils.ioClose(fileOutputStream);
                }
            }
        }).start();
    }

代码还是要敲的，敲了才算你自己的，看懂了还不够！视频课程已经上传，同学们也可以去看视频学习。

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