ClassCastException with JsonView and Optional in controller

[goeh]

Expected Behavior

A controller method with the following signature should return data:

    @JsonView(Views.Public.class)
    @Get("/optional")
    public Optional<User> getUserOptional() {
        return Optional.of(new User(1, "Joe", "secret"));
    }

public class Views {
    public static class Public {}
    public static class Secret extends Public {}
}

Actual Behaviour

java.lang.ClassCastException: class com.example.User cannot be cast to class java.util.Optional (com.example.User is in unnamed module of loader 'app'; java.util.Optional is in module java.base of loader 'bootstrap')
	at io.micronaut.serde.support.serdes.OptionalSerde$1.serialize(OptionalSerde.java:53)
	at io.micronaut.serde.jackson.JacksonJsonMapper.writeValue(JacksonJsonMapper.java:187)
	at io.micronaut.serde.jackson.JacksonJsonMapper.writeValueAsBytes(JacksonJsonMapper.java:285)
	at io.micronaut.json.codec.MapperMediaTypeCodec.encode(MapperMediaTypeCodec.java:265)
	at io.micronaut.http.server.netty.jackson.JsonViewServerFilter.lambda$doFilter$1(JsonViewServerFilter.java:102)
	at reactor.core.publisher.MonoCallable.call(MonoCallable.java:72)
	at reactor.core.publisher.FluxSubscribeOnCallable$CallableSubscribeOnSubscription.run(FluxSubscribeOnCallable.java:228)

If I comment out the JsonView annotation, the exception is not thrown.

Steps To Reproduce

1. Annotate an optional controller method with JsonView
2. Send a http request to the endpoint
3. See ClassCastException

Environment Information

• MacOS 14.5
• JDK "21.0.2" 2024-01-16 LTS

Example Application

https://github.com/goeh/micronaut-jsonview-issue

Version

4.5.0