To fix how the deserializer interacts with its parent class

[qbuzzdaan]

Changes how an StdDeserializer<A> of a specific type A deserializes into an A. We noticed the static block filling the mappings passed to the JSON.registerDiscriminator(A.class, "type", mappings) was only called after the first call to the deserializer, causing the first result to have an setActualInstance call of the wrong subtype of A. This is because the static block is part of A, while the StdDeserializer<A> is a static subclass of A. Changing the reference to A.class into an actual instance of A by the new A().getClass() causes the static block to be called on time.

to fix #18975

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[wing328]

thanks for the PR.

please follow step 3 to update the samples so that the CI can verify the change.

[qbuzzdaan]

First commit/PR here, trying my best to follow the steps/guidelines etc :) Ran the commands of steps 3, there are no changes in the samples as it seems.

[wing328]

can you please share a spec to reproduce the issue?

[qbuzzdaan]

I've added the issue_18975.yaml spec. Running step 3 again again didn't yield any changes in my repository.

[wing328]

tested locally and the output copmiles without issue. let's give it a try

i'll add a test after merging this PR

thanks again for the PR