Shade JSON API in annotation-processor

[snicoll]

#9248 is now generating a warning if two competing JSON APIs are on the classpath.

As far as I can see, spring-boot-configuration-processor is the only component that pulls that in. An annotation processor is typically added via an "optional" dependency but, regardless, that JSON API becomes available to the project's classpath.

Two side effects:

• You may want to code against that API and then be surprised that your code doesn't work because the annotation processor is (and should not be) added as transitive
• If you add a JSON API (as you should) you automatically get a duplicate warning message and no way to fix it.

Also, the JSON api we use is not in dependency management so users can't even chose that if they don't have an opinion regarding the implementation.

[snicoll]

Actually JSONAssert also brings that API so I think we should at least provide dependency management for it. Otherwise, how are we supposed to get rid of the warning?

[philwebb]

I think we had this shaded at one point but it broke in the IDE.

[wilkinsona]

I'm not sure I understand the benefits of shading the API for the first problem. How will that stop a user from accidentally coding against it? We'd need something that's package-private to avoid that would we not?

[snicoll]

That's what I meant.

[philwebb]

We did a shade/relocate before. See the now reverted 45d5b60 and issue #7883

[philwebb]

@snicoll In fact I think this can be marked as duplicate?

[snicoll]

Not really. I said I would investigate and I did not. So I'd like to do that as shading is the right call for this IMO.