[hibernate-dev] HCANN, AnnotationFactory and TCCL

Steve Ebersole steve at hibernate.org
Thu May 28 10:23:59 EDT 2015

Ok, then everyone seems to be on board with the simple approach.  Awesome!
FWIW I'd have to imagine this is close to what the VM does for annotations
anyway.  So that's an extra win in my book.

On Thu, May 28, 2015 at 5:08 AM, Sanne Grinovero <sanne at hibernate.org>

With that TCCL trick in place it seems it was possible to have the
> module actually use a set of annotations provided by the user, to
> override those (with same name) already provided by ORM. If that was
> meant as a "feature" I'd be glad to see it killed.

I think the "intent" was just non-intent tbh.  It just used TCCL rather
than allowing for specifying which ClassLoader to use because it was
"easier".  Any expectation beyond that *should* break imho.

The above approach seems nicer as you already have the Class,
> otherwise I'd prefer to see such helpers to always allow an explicit
> ClassLoader.
> I don't think you have to worry about ORM requiring new versions of
> HCANN occasionally, we all have to make changes to keep up anyway and
> a version upgrade is easy enough.

Well especially if we are  bumping the release family from 4.0 to 4.1

> We did have a problem with recent "planet alignment" efforts of
> versions on other platforms though, which was caused by a significant
> semantic change of a similar classloader improvement, and some people
> had upgraded the micro version of HCANN without enough testing. As far
> as I remember the dangerous upgrade was the upgrade from HCANN
> 4.0.1.Final to 4.0.5.Final, which breaks Hibernate ORM 4.2 within the
> app server.
> In retrospective we should have increased the minor version of HCANN,
> so maybe you could do that now when fixing the TCCL issue?

Yep, I probably should have done that back when.  I will do it now.  4.1?

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