ApplicationListenerMethodAdapter supports non-matching generic events

[odrotbohm]

ApplicationListenerMethodAdapter wrongly indicates it would support a generic event type exposing unresolved generics, even if there's no type relationship between the events at all. See the following, failing test case:

class ApplicationListenerMethodAdapterTests {

	@Test
	void testName() throws Exception {

		var method = ApplicationListenerMethodAdapterTests.class.getDeclaredMethod("listener", SomeOtherEvent.class);
		var adapter = new ApplicationListenerMethodAdapter(null, ApplicationListenerMethodAdapterTests.class, method);

		assertThat(adapter.supportsEventType(ResolvableType.forClass(SomeGenericEvent.class))).isFalse();
	}

	@EventListener
	void listener(SomeOtherEvent event) {}

	static class SomeGenericEvent<T> {}

	static class SomeOtherEvent {}
}

Note how the adapter signals the event listener method would support SomeGenericEvent when it clearly doesn't.

[sbrannen]

Thanks for reporting the issue, @odrotbohm.

It looks like the fallback to return eventType.hasUnresolvableGenerics() in ApplicationListenerMethodAdapter.supportsEventType(ResolvableType) is the culprit.

[odrotbohm]

Yes, I ended up at the same place. Wonder whether this needs to be augmented with at least a raw type assignability check?