DownloadHelper.java 文件源码

/**
 * check url
 *
 * @param url url
 * @return empty
 */
private ObservableSource<Object> checkUrl(final String url) {
    return downloadApi.check(url)
            .flatMap(new Function<Response<Void>, ObservableSource<Object>>() {
                @Override
                public ObservableSource<Object> apply(@NonNull Response<Void> resp)
                        throws Exception {
                    if (!resp.isSuccessful()) {
                        return checkUrlByGet(url);
                    } else {
                        return saveFileInfo(url, resp);
                    }
                }
            })
            .compose(retry(REQUEST_RETRY_HINT, maxRetryCount));
}