java - URLConnection 超时问题

Question

我正在使用 android 应用程序，我正在从 url 下载文件。一切正常，但是当互联网连接介于两者之间(打开连接后)时，下载超时永远不会发生并且连接永远不会结束。

给我一​​个解决这个问题的方案

        **URL url = new URL("fileURL");
        URLConnection connection = url.openConnection();
        connection.setConnectTimeout(5000);
        File file = new File(context.getFilesDir(), "" + filename);
        // getting file length
        int lenghtOfFile = connection.getContentLength();
        // input stream to read file - with 8k buffer
        InputStream input = new BufferedInputStream(url.openStream(), 8192);
        // Output stream to write file
        OutputStream output = new FileOutputStream(file);
        byte data[] = new byte[1024];
        long total = 0;
        while ((count = input.read(data)) != -1) {
            total += count;
            int status = (int) ((total * 100) / lenghtOfFile);
            publishProgress("" + status);
            // writing data to file
            output.write(data, 0, count);
        }
        // flushing output
        output.flush();
        // closing streams
        output.close();
        input.close()**

Answer 1

您可以使用 Retrofit Library 从服务器下载文件，

Retrofit 内部使用 OkHttp

请引用以下网址，

https://futurestud.io/tutorials/retrofit-2-how-to-download-files-from-server

final FileDownloadService downloadService =
            ServiceGenerator.createService(FileDownloadService.class);

    Call<ResponseBody> call =
            downloadService.downloadFileWithDynamicUrlSync(fileUrl);
    call.enqueue(new Callback<ResponseBody>() {
        @Override
        public void onResponse(Call<ResponseBody> call, final Response<ResponseBody>
                response) {
            if (response.isSuccessful()) {
                Log.d(TAG, "server contacted and has file");

                new AsyncTask<Void, Void, Void>() {
                    @Override
                    protected Void doInBackground(Void... voids) {
                        boolean writtenToDisk = writeResponseBodyToDisk(FileDownloadActivity.this, response.body(), null);

                        Log.d(TAG, "file download was a success? " + writtenToDisk);
                        return null;
                    }
                }.execute();
            } else {
                Log.d(TAG, "server contact failed");
            }
        }

而且你还可以对大文件使用@Streaming注解。 Retrofit 也将处理大文件下载