// Get the image from the filesystem if it exists or download from network
private Observable<Page> getOrDownloadImage(final Page page, Download download) {
// If the image URL is empty, do nothing
if (page.getImageUrl() == null) return Observable.just(page);
String filename = getImageFilename(page);
File imagePath = new File(download.directory, filename);
// If the image is already downloaded, do nothing. Otherwise download from network
Observable<Page> pageObservable =
isImageDownloaded(imagePath)
? Observable.just(page)
: downloadImage(page, download.source, download.directory, filename);
return pageObservable
// When the image is ready, set image path, progress (just in case) and status
.doOnNext(
p -> {
page.setImagePath(imagePath.getAbsolutePath());
page.setProgress(100);
download.downloadedImages++;
page.setStatus(Page.READY);
})
// Mark this page as error and allow to download the remaining
.onErrorResumeNext(
e -> {
page.setProgress(0);
page.setStatus(Page.ERROR);
return Observable.just(page);
});
}
@Test
@SuppressWarnings("unchecked")
public void testThreadName() throws InterruptedException {
System.out.println("Main Thread: " + Thread.currentThread().getName());
Observable<String> obs = Observable.just("one", null, "two", "three", "four");
Observer<String> observer = mock(Observer.class);
final String parentThreadName = Thread.currentThread().getName();
final CountDownLatch completedLatch = new CountDownLatch(1);
// assert subscribe is on main thread
obs =
obs.doOnNext(
new Action1<String>() {
@Override
public void call(String s) {
String threadName = Thread.currentThread().getName();
System.out.println(
"Source ThreadName: " + threadName + " Expected => " + parentThreadName);
assertEquals(parentThreadName, threadName);
}
});
// assert observe is on new thread
obs.observeOn(Schedulers.newThread())
.doOnNext(
new Action1<String>() {
@Override
public void call(String t1) {
String threadName = Thread.currentThread().getName();
boolean correctThreadName = threadName.startsWith("RxNewThreadScheduler");
System.out.println(
"ObserveOn ThreadName: " + threadName + " Correct => " + correctThreadName);
assertTrue(correctThreadName);
}
})
.finallyDo(
new Action0() {
@Override
public void call() {
completedLatch.countDown();
}
})
.subscribe(observer);
if (!completedLatch.await(1000, TimeUnit.MILLISECONDS)) {
fail("timed out waiting");
}
verify(observer, never()).onError(any(Throwable.class));
verify(observer, times(5)).onNext(any(String.class));
verify(observer, times(1)).onCompleted();
}