2.x: CreateEmitter throws when onError called after dispose unlike 1.x

I have these two tests which behave differently in 1.x and 2.x.

@org.junit.Test
public void testRxJava1() throws Exception {
	Subscription subscription = rx.Observable.fromEmitter(emitter -> {
		emitter.onNext(1);
		emitter.setCancellation(() -> emitter.onError(new IllegalArgumentException()));
	}, Emitter.BackpressureMode.NONE)
			.subscribe(
				integer -> System.out.println(integer),
				throwable -> throwable.printStackTrace()
			);

	subscription.unsubscribe();
}

@org.junit.Test
public void testRxJava2() throws Exception {
	Disposable disposable = Observable.create(emitter -> {
		emitter.onNext(1);
		emitter.setCancellable(() -> emitter.onError(new IllegalArgumentException()));
	}).subscribe(
		integer -> System.out.println(integer),
		throwable -> throwable.printStackTrace()
	);

	disposable.dispose();
}

The 2.x CreateEmitter ends up throwing the exception as an uncaught exception, the 1.x Emitter just returns if the Subscription has already been unsubscribed.

The Wiki at Entering the Reactive World makes it sounds like both should behave the same.

What would be the correct usage in 2.x to get the same behaviour as in 1.x and not crashing the Application with the emitter.onError(...) call?

[akarnokd]

See FlowableEmitter.tryOnError and similar methods since 2.1.1 .

[Mauin]

Working solution is to manually check if the emitter is not disposed before calling emitter.onError() to prevent the throw from happening. Mainly just wanted to point out the difference in Emitters between 1.x and 2.x even though the Wiki states they should be the same