[hibernate-dev] Hibernate Rx: Remove Optional from API

[Sanne Grinovero]

I would agree with you all about the general sentiment against the use
of Optional, but there's one use case in which I think it might make
sense (although bear with me as I've never really used it much yet) :

there's several methods on the standard Session and EntityManager in
Hibernate ORM to fetch a single entity: load/find/get/...

Even after all these years, I always have to open the Javadoc to
remember which ones are making assumptions about the entity existence
in the database (so could return a proxy even if the object doesn't
actually existin the DB), and which ones are going to check first in
the DB, possibly returning null.

Wouldn't Optional be great there to express the doubt vs the certainty
of it returning something?

Similarly in xToOne associations, having to remember to set the
"optional" attribute, or having business code having to match the
mapping is not ideal. That's perhaps unrelated, as this second point
is more about how users should express mappings rather than how we
expose APIs, but I mean it as an example to not necessarily go to the
extreme of ignoring that it might have some use in some selected
cases.

Thanks,
Sanne

On Thu, 16 Apr 2020 at 11:44, Davide D'Alto <daltodavide at gmail.com> wrote:
>
> Hi,
> Gavin sent this PR: https://github.com/hibernate/hibernate-rx/pull/93
>
> It removes Optional from the API, for example:
>
> <T> CompletionStage<Optional<T>> fetch(T association);
>
> becomes:
>
> <T> CompletionStage<T> fetch(T association);
>
> Is there anybody here with strong opinions about keeping Optional in the
> API?
>
> Thanks,
> Davide
> _______________________________________________
> hibernate-dev mailing list
> hibernate-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/hibernate-dev
>