@Test
public void mustBeAbleToRecover() throws Exception {
final ManualProbe<Integer> publisherProbe = TestPublisher.manualProbe(true, system);
final JavaTestKit probe = new JavaTestKit(system);
final Source<Integer, NotUsed> source =
Source.fromPublisher(publisherProbe)
.map(
elem -> {
if (elem == 1) throw new RuntimeException("ex");
else return elem;
})
.recover(new PFBuilder<Throwable, Integer>().matchAny(ex -> 0).build());
final CompletionStage<Done> future =
source.runWith(
Sink.foreach(elem -> probe.getRef().tell(elem, ActorRef.noSender())), materializer);
final PublisherProbeSubscription<Integer> s = publisherProbe.expectSubscription();
s.sendNext(0);
probe.expectMsgEquals(0);
s.sendNext(1);
probe.expectMsgEquals(0);
future.toCompletableFuture().get(200, TimeUnit.MILLISECONDS);
}
@Test
public void mustBeAbleToUseDropWhile() throws Exception {
final JavaTestKit probe = new JavaTestKit(system);
final Source<Integer, NotUsed> source =
Source.from(Arrays.asList(0, 1, 2, 3))
.dropWhile(
new Predicate<Integer>() {
public boolean test(Integer elem) {
return elem < 2;
}
});
final CompletionStage<Done> future =
source.runWith(
Sink.foreach(elem -> probe.getRef().tell(elem, ActorRef.noSender())), materializer);
probe.expectMsgEquals(2);
probe.expectMsgEquals(3);
future.toCompletableFuture().get(200, TimeUnit.MILLISECONDS);
}
@Test
public void demonstrateFilterAndMap() {
final SilenceSystemOut.System System = SilenceSystemOut.get();
// #first-sample
// #authors-filter-map
final Source<Author, NotUsed> authors =
tweets.filter(t -> t.hashtags().contains(AKKA)).map(t -> t.author);
// #first-sample
// #authors-filter-map
new Object() {
// #authors-collect
JavaPartialFunction<Tweet, Author> collectFunction =
new JavaPartialFunction<Tweet, Author>() {
public Author apply(Tweet t, boolean isCheck) {
if (t.hashtags().contains(AKKA)) {
if (isCheck) return null; // to spare the expensive or side-effecting code
return t.author;
} else {
throw noMatch();
}
}
};
final Source<Author, NotUsed> authors = tweets.collect(collectFunction);
// #authors-collect
};
// #first-sample
// #authors-foreachsink-println
authors.runWith(Sink.foreach(a -> System.out.println(a)), mat);
// #first-sample
// #authors-foreachsink-println
// #authors-foreach-println
authors.runForeach(a -> System.out.println(a), mat);
// #authors-foreach-println
}
@Test
public void mustBeAbleToCombine() throws Exception {
final JavaTestKit probe = new JavaTestKit(system);
final Source<Integer, NotUsed> source1 = Source.from(Arrays.asList(0, 1));
final Source<Integer, NotUsed> source2 = Source.from(Arrays.asList(2, 3));
final Source<Integer, NotUsed> source =
Source.combine(
source1,
source2,
new ArrayList<Source<Integer, ?>>(),
width -> Merge.<Integer>create(width));
final CompletionStage<Done> future =
source.runWith(
Sink.foreach(elem -> probe.getRef().tell(elem, ActorRef.noSender())), materializer);
probe.expectMsgAllOf(0, 1, 2, 3);
future.toCompletableFuture().get(200, TimeUnit.MILLISECONDS);
}
@Test
public void mustBeAbleToUseIntersperse() throws Exception {
final JavaTestKit probe = new JavaTestKit(system);
final Source<String, NotUsed> source =
Source.from(Arrays.asList("0", "1", "2", "3")).intersperse("[", ",", "]");
final CompletionStage<Done> future =
source.runWith(
Sink.foreach(elem -> probe.getRef().tell(elem, ActorRef.noSender())), materializer);
probe.expectMsgEquals("[");
probe.expectMsgEquals("0");
probe.expectMsgEquals(",");
probe.expectMsgEquals("1");
probe.expectMsgEquals(",");
probe.expectMsgEquals("2");
probe.expectMsgEquals(",");
probe.expectMsgEquals("3");
probe.expectMsgEquals("]");
future.toCompletableFuture().get(200, TimeUnit.MILLISECONDS);
}