改造 2 文件 down/upload

Question

我正在尝试 down/upload 一个带有 retrofit 2 的文件，但找不到任何关于如何操作的教程示例。我的下载密码是：

@GET("documents/checkout")
public Call<File> checkout(@Query(value = "documentUrl") String documentUrl, @Query(value = "accessToken") String accessToken, @Query(value = "readOnly") boolean readOnly);

和

Call<File> call = RetrofitSingleton.getInstance(serverAddress)
                .checkout(document.getContentUrl(), apiToken, readOnly[i]);
call.enqueue(new Callback<File>() {
        @Override
        public void onResponse(Response<File> response,
                Retrofit retrofit) {
            String fileName = document.getFileName();
            try {
                System.out.println(response.body());
                long fileLength = response.body().length();
                InputStream input = new FileInputStream(response.body());
                File path = Environment.getExternalStorageDirectory();
                File file = new File(path, fileName);
                BufferedOutputStream output = new BufferedOutputStream(
                        new FileOutputStream(file));
                byte data[] = new byte[1024];

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

                output.flush();

                output.close();
            } catch (IOException e) {
                String logTag = "TEMPTAG";
                Log.e(logTag, "Error while writing file!");
                Log.e(logTag, e.toString());
            }
        }
        @Override
        public void onFailure(Throwable t) {
            // TODO: Error handling
            System.out.println(t.toString());
        }
    });

我试过呼叫和呼叫，但似乎没有任何效果。

server-side 代码在正确设置 headers 和 mime 类型后将文件的字节写入 HttpServletResponse 的输出流。

我做错了什么？

最后上传代码：

@Multipart
@POST("documents/checkin")
public Call<String> checkin(@Query(value = "documentId") String documentId, @Query(value = "name") String fileName, @Query(value = "accessToken") String accessToken, @Part("file") RequestBody file);

和

RequestBody requestBody = RequestBody.create(MediaType.parse(document.getMimeType()), file);

            Call<String> call = RetrofitSingleton.getInstance(serverAddress).checkin(documentId, document.getFileName(), apiToken, requestBody);
            call.enqueue(new Callback<String>() {
                @Override
                public void onResponse(Response<String> response, Retrofit retrofit) {
                    System.out.println(response.body());
                }

                @Override
                public void onFailure(Throwable t) {
                    System.out.println(t.toString());
                }
            });

谢谢！

编辑：

回答后，下载只会产生损坏的文件（没有@Streaming），上传也不会。当我使用上面的代码时，服务器 returns 出现 400 错误。改成

后

RequestBody requestBody = RequestBody.create(MediaType.parse(document.getMimeType()), file);
            MultipartBuilder multipartBuilder = new MultipartBuilder();
            multipartBuilder.addFormDataPart("file", document.getFileName(), requestBody);

            Call<String> call = RetrofitSingleton.getInstance(serverAddress).checkin(documentId, document.getFileName(), apiToken, multipartBuilder.build());

，请求执行了，但是后端似乎没有收到文件。

后端代码：

@RequestMapping(value = "/documents/checkin", method = RequestMethod.POST)
public void checkInDocument(@RequestParam String documentId,
        @RequestParam String name, @RequestParam MultipartFile file,
        @RequestParam String accessToken, HttpServletResponse response)

我做错了什么？我能够使用普通 Java 的后端和 Apache HttpClient:

    MultipartEntityBuilder builder = MultipartEntityBuilder.create();
    builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
    builder.addBinaryBody("file", new File("E:\temp\test.jpg"));
    HttpEntity httpEntity = builder.build();
    System.out.println("HttpEntity " + EntityUtils.toString(httpEntity.));
    HttpPost httpPost = new HttpPost(uri);
    httpPost.setEntity(httpEntity);

编辑 v2

对于任何感兴趣的人，上传和下载现在都可以：这些是解决方案：

服务：

@GET("documents/checkout")
public Call<ResponseBody> checkout(@Query(value = "documentUrl") String documentUrl, @Query(value = "accessToken") String accessToken, @Query(value = "readOnly") boolean readOnly);

@Multipart
@POST("documents/checkin")
public Call<String> checkin(@Query(value = "documentId") String documentId, @Query(value = "name") String fileName, @Query(value = "accessToken") String accessToken, @Part("file") RequestBody file);

下载码：

    Call<ResponseBody> call = RetrofitSingleton.getInstance(serverAddress)
                .checkout(document.getContentUrl(), apiToken, readOnly[i]);
        call.enqueue(new Callback<ResponseBody>() {
            @Override
            public void onResponse(Response<ResponseBody> response,
                    Retrofit retrofit) {
                String fileName = document.getFileName();

                try {
                    File path = Environment.getExternalStorageDirectory();
                    File file = new File(path, fileName);
                    FileOutputStream fileOutputStream = new FileOutputStream(file);
                    IOUtils.write(response.body().bytes(), fileOutputStream);
                } catch (IOException e) {
                    Log.e(logTag, "Error while writing file!");
                    Log.e(logTag, e.toString());
                }
            }

            @Override
            public void onFailure(Throwable t) {
                // TODO: Error handling
                System.out.println(t.toString());
            }
        });

上传代码：

    Call<String> call = RetrofitSingleton
                    .getInstance(serverAddress).checkin(documentId,
                            document.getFileName(), apiToken,
                            multipartBuilder.build());
            call.enqueue(new Callback<String>() {
                @Override
                public void onResponse(Response<String> response,
                        Retrofit retrofit) {
                    // Handle response here
                }

                @Override
                public void onFailure(Throwable t) {
                    // TODO: Error handling
                    System.out.println("Error");
                    System.out.println(t.toString());
                }
            });

Answer 1

对于下载，您可以使用 ResponseBody 作为您的 return 类型 --

@GET("documents/checkout")
@Streaming
public Call<ResponseBody> checkout(@Query("documentUrl") String documentUrl, @Query("accessToken") String accessToken, @Query("readOnly") boolean readOnly);

并且您可以在回调中获得 ResponseBody 输入流 --

Call<ResponseBody> call = RetrofitSingleton.getInstance(serverAddress)
            .checkout(document.getContentUrl(), apiToken, readOnly[i]);

call.enqueue(new Callback<ResponseBody>() {
        @Override
        public void onResponse(Response<ResponseBody> response,
                Retrofit retrofit) {
            String fileName = document.getFileName();
            try {
                InputStream input = response.body().byteStream();
                //  rest of your code

如果您的服务器正确处理了多部分消息，您的上传乍一看没问题。它在工作吗？如果不是，你能解释一下故障模式吗？您也可以通过不使其成为多部分来简化。删除@Multipart注释并将@Path转换为@Body——

@POST("documents/checkin")
public Call<String> checkin(@Query("documentId") String documentId, @Query("name") String fileName, @Query("accessToken") String accessToken, @Body RequestBody file);

Answer 2

我使用的是改造 2.0.0-beta2，使用多部分请求上传图片时遇到问题。我用这个答案解决了它：

我的关键是使用标准 POST 和 MultipartRequestBody 而不是 @Multipart 带注释的请求。

这是我的代码：

改装服务class

@POST("photo")
Call<JsonElement> uploadPhoto(@Body RequestBody imageFile, @Query("sessionId"));

用法来自 activity，片段：

RequestBody fileBody = RequestBody.create(MediaType.parse("image/jpeg"), imageFile);
MultipartBuilder multipartBuilder = new MultipartBuilder();
multipartBuilder.addFormDataPart("photo", imageFile.getName(), fileBody);
RequestBody fileRequestBody = multipartBuilder.build();

//call
mRestClient.getRetrofitService().uploadProfilePhoto(fileRequestBody, sessionId);

Answer 3

我有同样的问题，我找到了上传文件的解决方案，在此处描述

Answer 4

我也遇到了这个问题，这就是我尝试解决问题的方法 (RETROFIT 2)

 //1. What We Need From Server ( upload.php Script )
    public class FromServer {
        String result;
    }

    //2. Which Interface To Communicate Our upload.php Script?
    public interface ServerAPI {

        @Multipart
        @POST("upload.php")//Our Destination PHP Script
        Call<List<FromServer>> upload(
                @Part("file_name") String file_name,
                @Part("file") RequestBody description);

         Retrofit retrofit =
                new Retrofit.Builder()
                        .baseUrl("http://192.168.43.135/retro/") // REMEMBER TO END with /
                        .addConverterFactory(GsonConverterFactory.create())
                 .build();
    }


    //3. How To Upload
    private void upload(){

            ServerAPI api = ServerAPI.retrofit.create(ServerAPI.class);

            File from_phone = FileUtils.getFile(Environment.getExternalStorageDirectory()+"/aa.jpg"); //org.apache.commons.io.FileUtils
            RequestBody to_server = RequestBody.create(MediaType.parse("multipart/form-data"), from_phone);

            api.upload(from_phone.getName(),to_server).enqueue(new Callback<List<FromServer>>() {
                @Override
                public void onResponse(Call<List<FromServer>> call, Response<List<FromServer>> response) {
                    Toast.makeText(MainActivity.this, response.body().get(0).result, Toast.LENGTH_SHORT).show();
                }
                @Override
                public void onFailure(Call<List<FromServer>> call, Throwable t) { }
            });


         }

//4. upload.php
<?php

    $pic = $_POST['file_name'];

    $pic = str_replace("\"", "", $pic); //REMOVE " from file name
    if(file_exists($pic)){unlink($pic);}

    $f = fopen($pic, "w");
    fwrite($f,$_POST['file']);
    fclose($f);

    $arr[] = array("result"=>"Done");
    print(json_encode($arr));
?>

Answer 5

Image Download using Retrofit 2.0

可以参考教程

图片下载暂时可以参考以下功能：

void getRetrofitImage() {

    Retrofit retrofit = new Retrofit.Builder()
            .baseUrl(url)
            .addConverterFactory(GsonConverterFactory.create())
            .build();

    RetrofitImageAPI service = retrofit.create(RetrofitImageAPI.class);

    Call<ResponseBody> call = service.getImageDetails();

    call.enqueue(new Callback<ResponseBody>() {
        @Override
        public void onResponse(Response<ResponseBody> response, Retrofit retrofit) {

            try {

                Log.d("onResponse", "Response came from server");

                boolean FileDownloaded = DownloadImage(response.body());

                Log.d("onResponse", "Image is downloaded and saved ? " + FileDownloaded);

            } catch (Exception e) {
                Log.d("onResponse", "There is an error");
                e.printStackTrace();
            }

        }

        @Override
        public void onFailure(Throwable t) {
            Log.d("onFailure", t.toString());
        }
    });
}

以下是使用Retrofit 2.0的文件处理部分图片下载

private boolean DownloadImage(ResponseBody body) {

    try {
        Log.d("DownloadImage", "Reading and writing file");
        InputStream in = null;
        FileOutputStream out = null;

        try {
            in = body.byteStream();
            out = new FileOutputStream(getExternalFilesDir(null) + File.separator + "AndroidTutorialPoint.jpg");
            int c;

            while ((c = in.read()) != -1) {
                out.write(c);
            }
        }
        catch (IOException e) {
            Log.d("DownloadImage",e.toString());
            return false;
        }
        finally {
            if (in != null) {
                in.close();
            }
            if (out != null) {
                out.close();
            }
        }

        int width, height;
        ImageView image = (ImageView) findViewById(R.id.imageViewId);
        Bitmap bMap = BitmapFactory.decodeFile(getExternalFilesDir(null) + File.separator + "AndroidTutorialPoint.jpg");
        width = 2*bMap.getWidth();
        height = 6*bMap.getHeight();
        Bitmap bMap2 = Bitmap.createScaledBitmap(bMap, width, height, false);
        image.setImageBitmap(bMap2);

        return true;

    } catch (IOException e) {
        Log.d("DownloadImage",e.toString());
        return false;
    }
}

希望对您有所帮助。祝一切顺利。快乐编码:)

改造 2 文件 down/upload

Retrofit 2 file down/upload

upload

android

download

retrofit