从OKHTTP下载二进制文件

Question

我在我的Android应用程序中使用OKHTTP客户端进行网络连接.

此示例显示如何上载二进制文件.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.

以下是该示例的列表:

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);
        }
    }
}

简单获取请求的当前代码是:

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();

现在我如何将响应转换为InputStream.类似于响应Apache HTTP Client的OkHttp响应:

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

---

编辑

从下面接受的答案.我修改过的代码:

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();

Answer 1

对于它的价值,我建议response.body().source()从okio(因为OkHttp本身已经支持它),以便更轻松地操作下载文件时可能出现的大量数据.

@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,文档中的一些优点:

此接口在功能上等同于InputStream.当消费数据是异构时,InputStream需要多个层:用于原始值的DataInputStream,用于缓冲的BufferedInputStream和用于字符串的InputStreamReader.该类使用BufferedSource来实现上述所有功能.Source避免了不可能实现的available()方法.相反,调用者指定它们需要多少字节.

Source省略了InputStream跟踪的unsafe-to-compose标记和重置状态; 调用者只是缓冲他们需要的东西.

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返回257个可能值中的一个.

并且source有一个更强大的跳过方法:BufferedSource.skip(long)不会过早返回.

Answer 2

从OKHTTP获取ByteStream

我一直在OkHttp的文档中挖掘你需要这样做

使用此方法:

response.body().byteStream()将返回一个InputStream

所以你可以简单地使用BufferedReader或任何其他替代方案

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();

Answer 3

下载的最佳选择(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();
}

Answer 4

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);
}

Answer 5

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);


                }
            });

Answer 6

基于 Kiddouk 答案的 Kotlin 版本

 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()