+1
Le lun. 7 févr. 2022 à 12:20, Stefan Seifert
<stefan.seif...@diva-e.com.invalid> a écrit :
> i agree with your opinion, and it's backed by the spec/javadocs.
> in most cases the consumer will access the bindings from an actual script
> (e.g. HTL), and in that case it should not make any difference for them.
>
> stefan
>
> >-----Original Message-----
> >From: Jörg Hoh <jhoh...@googlemail.com.INVALID>
> >Sent: Friday, February 4, 2022 12:01 PM
> >To: Sling Developers List <dev@sling.apache.org>
> >Subject: [Scripting] Bindings returning null
> >
> >Hi,
> >
> >I am currently working on a number of smaller performance improvements,
> and
> >I found that some BindingsValuesProvider could benefit from providings
> >lazily. In that case the binding is added, but the value is only resolved
> >when the value of the binding is actually needed, instead of resolving
> them
> >when adding the binding [1]. As these bindings are added very often, but
> >not always used, a small improvement in the area of a few hundred
> >microseconds can accumulate to a 2-digit number of milliseconds for a
> >complex request;
> >
> >The implementations of the BindingValuesProvider#addBindings() currently
> >often perform checks if the binding should be added at all. In the case of
> >a failed check the binding would not be added at all.
> > With the dynamic resolution this is hardly possible, it would defeat the
> >purpose of delaying the resolution (including these checks) to a time when
> >it's absolutely necessary. In the case of the dynamic resolution with a
> >failed check this just leaves the option to return "null" for that
> binding.
> >
> >The javax.script.Bindings#get spec [2] allows to return null in 2 cases:
> >* the mapping is not present
> >* the mapping returns a null
> >
> >So technically this change is covered by the spec, but I don't know if all
> >users of the bindings always check for null but have used some other
> >approach instead:
> >
> >if (bindings.containsKey(BINDING)) {
> > Object o = bindings.get(BINDING);
> > assertNotNull(o);
> >}
> >
> >which is incorrect according to the spec, but might have worked in the
> >past.
> >
> >In my opinion we should adjust these BindingsValuesProviders and require
> >the consumers of these bindings to make sure that they do the null-check
> as
> >required by the spec.
> >
> >WDYT?
> >
> >
> >Jörg
> >
> >
> >[1]
> >https://github.com/apache/sling-org-apache-sling-
>
> >api/blob/master/src/main/java/org/apache/sling/api/scripting/LazyBindings.j
> >ava
> >[2]
> >https://docs.oracle.com/javase/8/docs/api/javax/script/Bindings.html#get-
> >java.lang.Object-
> >
> >
> >--
> >Cheers,
> >Jörg Hoh,
> >
> >https://cqdump.joerghoh.de
> >Twitter: @joerghoh
>
