从OKHTTP下载二进制文件

我在我的Android应用程序中使用OKHTTP客户端进行联网。

此示例显示了如何上传二进制文件。我想知道如何使用OKHTTP客户端获取二进制文件下载的输入流。

这是示例的清单：

public class InputStreamRequestBody extends RequestBody {

    private InputStream inputStream;
    private MediaType mediaType;

    public static RequestBody create(final MediaType mediaType, 
            final InputStream inputStream) {
        return new InputStreamRequestBody(inputStream, mediaType);
    }

    private InputStreamRequestBody(InputStream inputStream, MediaType mediaType) {
        this.inputStream = inputStream;
        this.mediaType = mediaType;
    }

    @Override
    public MediaType contentType() {
        return mediaType;
    }

    @Override
    public long contentLength() {
        try {
            return inputStream.available();
        } catch (IOException e) {
            return 0;
        }
    }

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
        Source source = null;
        try {
            source = Okio.source(inputStream);
            sink.writeAll(source);
        } finally {
            Util.closeQuietly(source);
        }
    }
}

用于简单获取请求的当前代码为：

OkHttpClient client = new OkHttpClient();
request = new Request.Builder().url("URL string here")
                    .addHeader("X-CSRFToken", csrftoken)
                    .addHeader("Content-Type", "application/json")
                    .build();
response = getClient().newCall(request).execute();

现在如何将响应转换为InputStream。类似于Apache HTTP Client以下OkHttp响应的响应：

InputStream is = response.getEntity().getContent();

编辑

从下面接受答案。我修改的代码：

request = new Request.Builder().url(urlString).build();
response = getClient().newCall(request).execute();

InputStream is = response.body().byteStream();

BufferedInputStream input = new BufferedInputStream(is);
OutputStream output = new FileOutputStream(file);

byte[] data = new byte[1024];

long total = 0;

while ((count = input.read(data)) != -1) {
    total += count;
    output.write(data, 0, count);
}

output.flush();
output.close();
input.close();

从OKHTTP获取ByteStream

我一直在研究OkHttp的文档，您需要这样做

使用此方法：

response.body（）。byteStream（）将返回InputStream

因此您可以简单地使用BufferedReader或任何其他替代方法

OkHttpClient client = new OkHttpClient();
request = new Request.Builder().url("URL string here")
                     .addHeader("X-CSRFToken", csrftoken)
                     .addHeader("Content-Type", "application/json")
                     .build();
response = getClient().newCall(request).execute();

InputStream in = response.body().byteStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String result, line = reader.readLine();
result = line;
while((line = reader.readLine()) != null) {
    result += line;
}
System.out.println(result);
response.body().close();

对于它的价值，我会建议response.body().source()从奥基奥为了享受更简单的方法来处理下载文件时可以来的数据量大（因为OkHttp已经支持它本身）。

@Override
public void onResponse(Call call, Response response) throws IOException {
    File downloadedFile = new File(context.getCacheDir(), filename);
    BufferedSink sink = Okio.buffer(Okio.sink(downloadedFile));
    sink.writeAll(response.body().source());
    sink.close();
}

与InputStream相比，该文档具有两个优点：

此接口在功能上等效于InputStream。当消耗的数据是异构的时，InputStream需要多层：用于原始值的DataInputStream，用于缓冲的BufferedInputStream和用于字符串的InputStreamReader。此类针对上述所有内容使用BufferedSource。Source避免了无法实现的available（）方法。而是，调用者指定所需的字节数。

Source省略了InputStream跟踪的不安全的标记和重置状态。呼叫者只是缓冲他们需要的东西。

在实现源代码时，您不必担心单字节读取方法难以有效实现并且返回257个可能值之一的情况。

源具有更强大的跳过方法：BufferedSource.skip（long）不会过早返回。

最佳下载选项（基于源代码“ okio”）

private void download(@NonNull String url, @NonNull File destFile) throws IOException {
    Request request = new Request.Builder().url(url).build();
    Response response = okHttpClient.newCall(request).execute();
    ResponseBody body = response.body();
    long contentLength = body.contentLength();
    BufferedSource source = body.source();

    BufferedSink sink = Okio.buffer(Okio.sink(destFile));
    Buffer sinkBuffer = sink.buffer();

    long totalBytesRead = 0;
    int bufferSize = 8 * 1024;
    for (long bytesRead; (bytesRead = source.read(sinkBuffer, bufferSize)) != -1; ) {
        sink.emit();
        totalBytesRead += bytesRead;
        int progress = (int) ((totalBytesRead * 100) / contentLength);
        publishProgress(progress);
    }
    sink.flush();
    sink.close();
    source.close();
}

这是我如何使用Okhttp +奥基奥库，而每块下载后发布下载进度：

public static final int DOWNLOAD_CHUNK_SIZE = 2048; //Same as Okio Segment.SIZE

try {
        Request request = new Request.Builder().url(uri.toString()).build();

        Response response = client.newCall(request).execute();
        ResponseBody body = response.body();
        long contentLength = body.contentLength();
        BufferedSource source = body.source();

        File file = new File(getDownloadPathFrom(uri));
        BufferedSink sink = Okio.buffer(Okio.sink(file));

        long totalRead = 0;
        long read = 0;
        while ((read = source.read(sink.buffer(), DOWNLOAD_CHUNK_SIZE)) != -1) {
            totalRead += read;
            int progress = (int) ((totalRead * 100) / contentLength);
            publishProgress(progress);
        }
        sink.writeAll(source);
        sink.flush();
        sink.close();
        publishProgress(FileInfo.FULL);
} catch (IOException e) {
        publishProgress(FileInfo.CODE_DOWNLOAD_ERROR);
        Logger.reportException(e);
}

更好的解决方案是使用OkHttpClient作为：

OkHttpClient client = new OkHttpClient();

            Request request = new Request.Builder()
                    .url("http://publicobject.com/helloworld.txt")
                    .build();



            client.newCall(request).enqueue(new Callback() {
                @Override
                public void onFailure(Call call, IOException e) {
                    e.printStackTrace();
                }

                @Override
                public void onResponse(Call call, Response response) throws IOException {

                    if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

//                    Headers responseHeaders = response.headers();
//                    for (int i = 0; i < responseHeaders.size(); i++) {
//                        System.out.println(responseHeaders.name(i) + ": " + responseHeaders.value(i));
//                    }
//                    System.out.println(response.body().string());

                    InputStream in = response.body().byteStream();
                    BufferedReader reader = new BufferedReader(new InputStreamReader(in));
                    String result, line = reader.readLine();
                    result = line;
                    while((line = reader.readLine()) != null) {
                        result += line;
                    }
                    System.out.println(result);


                }
            });

Kodlin版本基于kiddouk的答案

 val request = Request.Builder().url(url).build()
 val response = OkHttpClient().newCall(request).execute()
 val downloadedFile = File(cacheDir, filename)
 val sink: BufferedSink = downloadedFile.sink().buffer()
 sink.writeAll(response.body!!.source())
 sink.close()