I would argue (and probably lose) that something that worked in 99% of cases
as expected would be better than something that never does.
I will reread Stuarts arguments, but it seems to me that we can specify how
equals works with client proxies.
On Tue, Oct 18, 2011 at 1:56 PM, Pete Muir <pmuir(a)redhat.com> wrote:
On 18 Oct 2011, at 21:42, Rick Hightower wrote:
> Currently the docs say this.... 5.4.2.
>
> •Behavior of all methods declared by java.lang.Object, except for
toString(), is undefined for a client proxy
> •Portable applications should not invoke any method declared by
java.lang.Object, except for toString(), on a client proxy
>
> I so don't agree with what is in the spec. now on this subject.
> (Realizing that it is a work in progress...)
Not really, this is unchanged since 1.0. We don't currently have plans to
change this.
>
> I think we should change this and call the underlying implementation for
these methods.
> Also equals and hashCode should work by unpacking and comparing the
contextual instance.
Please take a look at Stuart's follow up to Mark's email, he has
investigated the options thoroughly, and found there is no solution that can
correctly obey the rules for equals. For this reason it's better to keep it
unspecified, as it warns people not to rely on this behavior.
>
> Off topic....
>
> It would be nice if there was a utility API that implementations had to
implement that had these methods
>
>
> isProxy (lets you know if an object is a client proxy)
> getUnproxiedVersion (gives you the underlying unproxied version of the
object)
>
>
> (It may exist already.)
I don't believe there is, so file a CDI issue and we can discuss / add it.
It should be relatively trivial (require any client proxy to implement an
interface e.g. ClientProxy and provide a method on getUnderlying() or
similar).
>
>
> On Tue, Oct 18, 2011 at 10:17 AM, Mark Struberg <struberg(a)yahoo.de>
wrote:
> Hi folks!
>
> There is a problem still in the chain which is a bit more trickier. It's
about equals() on contextual references.
>
> If the 'other' instance which gets compared with is a proxy as well, then
we would first need to 'unpack' it and pass the underlying contextual
instance into the comparison implementation. Otherwise accessing private
fields from the 'other' will actually only hit the proxy, and not the
'real'
target.
>
> But otherwise it should work fine.
>
>
> Wdyt?
>
> 1.) Should we specify this?
See Stuart's response, I would be very leery of requiring behavior which
broke the fundamental contract of equals(). If we can't fully support the
correct behavior, it's better to leave it unportable.
>
> 2.) What is the expected behaviour?
>
> 3.) Do we like to specify equals() for beans at all?
> 4.) Is there some established behaviour in other frameworks which heavily
uses proxies?
Not AFAIK. We played around for ages with this in Seam and Weld, and have
something that gives you 99% correct behavior, but there are still edge
cases.
> 5.) Should we at least specify that 'non portable behaviour results'?
We do, see Rick's reference above.
>
>
> LieGrue,
> strub
>
>
>
> ----- Original Message -----
> > From: Pete Muir <pmuir(a)redhat.com>
> > To: Mark Struberg <struberg(a)yahoo.de>
> > Cc: cdi-dev(a)lists.jboss.org; Stuart Douglas <sdouglas(a)redhat.com>
> > Sent: Monday, March 14, 2011 12:52 PM
> > Subject: Re: [cdi-dev] calling 'equals' on a proxy?
> >
> > Stuart, you had this one worked out right? I believe the spec says the
behaviour
> > is unspecified.
> >
> > On 7 Mar 2011, at 15:52, Mark Struberg wrote:
> >
> >> Hi Pete, others!
> >>
> >> Do you remember our discussion about what should happen if equals()
gets
> > called on a proxy?
> >>
> >> Should it route to the equals method of the currently proxied
instance?
> >>
> >> LieGrue,
> >> strub
> >>
> >>
> >>
> >> _______________________________________________
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> >> cdi-dev(a)lists.jboss.org
> >>
https://lists.jboss.org/mailman/listinfo/cdi-dev
> >
>
>
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