public class Flight {
    @PreAuthorize("hasAuthority('airplane:read')")
    Double getAltitude() {
        return 35000d;
    }
}

// ...

var factory = new AuthorizationAdvisorProxyFactory();
var flight = new Flight();
assertThatNoException().isThrownBy(flight::getAltitude);
Flight proxied = (Flight) factory.proxy(flight);
assertThatExceptionOfType(AccessDeniedException.class).isThrownBy(proxied::getAltitude);

@Component
@AuthorizeReturnObject
public class FlightRepository {
    Iterator<Flight> findAll() {
        return List.of(new Flight()).iterator();
    }
}

// ...

@Component
@AuthorizeReturnObject
public class FlightRepository {
    Flux<Flight> findAll() {
        return Flux.just(new Flight());
    }
}

// ...

@Bean 
AuthorizationProxyFactoryPredicate skipValueTypes() {
    return SkipAuthorizationProxyFactoryPredicate.skipValueTypes();
}