@Override
    public void register(@NonNull Scheme scheme) {
        if (!schemes.contains(scheme)) {
            indexSpecRegistry.indexFor(scheme);
            schemes.add(scheme);
            getWatchers().forEach(watcher -> watcher.onChange(new SchemeRegistered(scheme)));
        }
    }
@Test
    void shouldThrowExceptionWhenNoGvkAnnotation() {
        class WithoutGvkExtension extends AbstractExtension {
        }

        assertThrows(IllegalArgumentException.class,
            () -> schemeManager.register(WithoutGvkExtension.class));
    }