@Test public void mustBeAbleToUseVoidTypeInForeach() { final JavaTestKit probe = new JavaTestKit(system); final java.lang.Iterable<String> input = Arrays.asList("a", "b", "c"); Source<String, NotUsed> ints = Source.from(input); final CompletionStage<Done> completion = ints.runForeach(elem -> probe.getRef().tell(elem, ActorRef.noSender()), materializer); completion.thenAccept(elem -> probe.getRef().tell(String.valueOf(elem), ActorRef.noSender())); probe.expectMsgEquals("a"); probe.expectMsgEquals("b"); probe.expectMsgEquals("c"); probe.expectMsgEquals("Done"); }