Amazon web services RXJava2+；AWS SDK:从AWS S3 TransferListener调用onError时获取UndeliverableException

我使用RXJava（RXAndroid）来序列化一组awss3传输请求

我正在使用AWS TransferUtility，它提供了一个异步TransferListener，可以获取进度和错误通知

我很难传播这些错误

我的代码是这样的

    for (final String subscription : subscriptions) {

        Observable<String> thisObservable = new Observable<String>() {
            @Override
            protected void subscribeActual(Observer<? super String> observer) {
                new S3Loader(subscription, observer).load();
                // The S3Loader uses AWS TransferListener to call onNext and onError of the observers
            }
        };

        observables.add(thisObservable);

        Log.v(this, "Added %s", subscription);

    }

    Observable.concat(observables)
            .subscribeOn(Schedulers.io())
            .observeOn(AndroidSchedulers.mainThread())
            .subscribe(new Observer<String>() {

                     @Override
                     public void onSubscribe(@NonNull Disposable d) {
                         Log.v(OperationalStatusFragment.this, "Subscribed...");
                     }

                     @Override
                     public void onNext(@NonNull String s) {
                         Log.v(OperationalStatusFragment.this, "Started weather operation \"%s\"", s);
                     }

                     @Override
                     public void onError(@NonNull Throwable e) {
                         Log.e(OperationalStatusFragment.this, "An error happened...");
                     }

                     @Override
                     public void onComplete() {
                         Log.v(OperationalStatusFragment.this, "Completed...");

                     }
                 }
    );

编辑2：以下是S3loader.load（）的外观：

public void load() {

    observer.onNext(subscription);

        AmazonS3Client s3Client = new AmazonS3Client();
        TransferUtility transferUtility = new TransferUtility(s3Client, context);
        TransferObserver observer = transferUtility.download(BUCKET, subscription, file);
        observer.setTransferListener(new TransferListener() {

            @Override
            public void onStateChanged(int id, TransferState state) {

                if (state == TransferState.COMPLETED) {
                    observer.onComplete();
                } else if (state == TransferState.FAILED) {
                    observer.onError(new IOException("An error happened"));
                } 
            }

            @Override
            public void onProgressChanged(int id, long bytesCurrent, long bytesTotal) {

            }

            @Override
            public void onError(int id, Exception e) {

                observer.onError(e);
            }
        });

}

---

显示实际的stacktrace以及如何实现S3Loader将非常有用。还有，为什么不使用

创建
？@akarnodkd，我添加了堆栈跟踪和加载代码。我没有使用create，因为我使用了
concat
。我不确定我是否也应该有一个
create
。RxJava的版本是什么？也请使用
observatable。create
遵守observatable协议。@akarnokd，这是RXJava2。你能不能在“可观察的。创造一个尊重可观察的协议”上说一点？
public void load() {

    observer.onNext(subscription);

        AmazonS3Client s3Client = new AmazonS3Client();
        TransferUtility transferUtility = new TransferUtility(s3Client, context);
        TransferObserver observer = transferUtility.download(BUCKET, subscription, file);
        observer.setTransferListener(new TransferListener() {

            @Override
            public void onStateChanged(int id, TransferState state) {

                if (state == TransferState.COMPLETED) {
                    observer.onComplete();
                } else if (state == TransferState.FAILED) {
                    observer.onError(new IOException("An error happened"));
                } 
            }

            @Override
            public void onProgressChanged(int id, long bytesCurrent, long bytesTotal) {

            }

            @Override
            public void onError(int id, Exception e) {

                observer.onError(e);
            }
        });

}