On 7/29/2016 4:24 AM, Andrew Dinn wrote:
On 28/07/16 23:05, Alex Buckley wrote:
Down-thread, Alan asked for examples of the changes you've made to a 3rd
party's descriptor, but I think you're raising "descriptor baked into a
3rd party jar" as a concern for modules delivered in the future rather
than for JAR files you have on hand today. I think this because Sanne
Grinovero spoke on 7/12 of CREATING descriptors from scratch:
"In fact in my team we also have experience "packaging" lots of these
OSS Java libraries into JBoss Modules, and have always appreciated that
- as an assembler - with JBoss Modules I can define the dependencies via
external metadata, without having to recompile or have to reassemble the
jar. As you [meaning John Rose] suggest, it is indeed useful to be able
to override the intent of the library authors, especially as different
libraries are developed by independent teams / communities / companies."
I assume the "intent of the library authors" is found in the POM, and he
translate it to module.xml [1] with occasional tweaks to add, remove,
and optionalize dependencies.
Am I on track?
Yes, you are on track. The problem I was referring to relates to the
future possibility of having to integrate Jigsaw-enabled components into
middleware tools like containers, specifically to whatever management
problems this may cause. The potential for complexity is twofold. A
container like EAP may be faced with having some of the component jars
it relies on being Jigsaw-modularized. It may also need to deploy
Jigsaw-modularized application jars which need to access the
functionality it manages. In both cases the specific problem I was
concerned with was the need to add, remove or optimize dependencies that
Sanne refers to.
Mark already discussed with Jason how a container can rewrite
descriptors as modules are being spun up [1] so I'm struggling to see
the problem unless there is some burning desire to rewrite the
descriptor by hand prior to run time. I can understand that if Sanne
takes third party JARs containing no descriptors, and manually creates
descriptors by spying on the POMs, then sure it's nice to keep the
descriptors external and the JARs unchanged ... but a Jigsaw modular JAR
already contains a descriptor that we assume is authoritative unless a
container is rewriting at run time.
Alex
[1] http://mail.openjdk.java.net/pipermail/jigsaw-dev/2016-July/008637.html
