android - 使用 Retrofit 2 上传文件时出错

Question

我正在尝试使用 Retrofit 2 将文件(图片)上传到服务器。我正在关注 tutorial乍一看这似乎很容易，但对我来说却行不通......

当我调用 API 函数时，我总是得到这个错误:

W/System.err: java.lang.ArrayIndexOutOfBoundsException: length=1; index=1
W/System.err:     at retrofit2.ServiceMethod$Builder.build(ServiceMethod.java:190)
W/System.err:     at retrofit2.Retrofit.loadServiceMethod(Retrofit.java:166)
W/System.err:     at retrofit2.Retrofit$1.invoke(Retrofit.java:145)
W/System.err:     at java.lang.reflect.Proxy.invoke(Proxy.java:393)
W/System.err:     at com.plante.android.cobalt.fragment.FragmentIncidentPlan.uploadFile(FragmentIncidentPlan.java:575)

这是我的 API 调用:

@Multipart
@POST(Constants.URL_UPLOAD)
Call<ResponseBody> upload(@Part RequestBody description,
                          @Part MultipartBody.Part file);

这是我用来上传文件的方法:

private void uploadFile(String path) {
    // create upload service client

    // use the FileUtils to get the actual file by uri
    File file = new File(path);
    Log.e(TAG, file.getAbsolutePath());

    // create RequestBody instance from file
    RequestBody requestFile =
            RequestBody.create(MediaType.parse("multipart/form-data"), file);

    // MultipartBody.Part is used to send also the actual file name
    MultipartBody.Part body =
            MultipartBody.Part.createFormData("picture", file.getName(), requestFile);

    // add another part within the multipart request
    String descriptionString = "hello, this is description speaking";
    RequestBody description =
            RequestBody.create(
                    MediaType.parse("multipart/form-data"), descriptionString);

    // finally, execute the request
    Call<ResponseBody> call = cobaltServices.upload(description, body);
    call.enqueue(new Callback<ResponseBody>() {
        @Override
        public void onResponse(Call<ResponseBody> call,
                               Response<ResponseBody> response) {
            Log.v("Upload", "success");
        }

        @Override
        public void onFailure(Call<ResponseBody> call, Throwable t) {
            Log.e("Upload error:", t.getMessage());
        }
    });
}

Answer 1

Exceptions 说第一个 @Part 不需要在注解中有名字。

@Multipart
@POST(Constants.URL_UPLOAD)
Call<ResponseBody> upload(@Part RequestBody description,
                          @Part MultipartBody.Part file);