Add option to generate a fully sealed model in the JavaSpring generator

[alex-nt]

Add option to generate a fully sealed model in the JavaSpring generator.
Related with #15586

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[martin-mfg]

Hi @alex-nt, thanks for the PR!

It generally looks good, but there are some special cases which need to be handled. When using your new feature on the input spec modules/openapi-generator/src/test/resources/3_0/oneOf_array.yaml, this is the generated code:

public sealed interface MyExampleGet200Response permits List<@Valid OneOf1> {

• HTML encoding needs to be disabled
• generics are not supported in the permits clause, afaik
• List shouldn't be in the permits list (same applies to other classes not generated by us)
• annotations are not supported in the permits clause, afaik

Could you fix these problems please?

It might also make sense to test with some other "oneOf" files from modules/openapi-generator/src/test/resources/3_0 to find further cases that need special handling.

[alex-nt]

@martin-mfg Thanks a lot, I'll look into all the oneOf samples, I only tested with the weirdest one and our own file 😅, that was quite naive from me.

[alex-nt]

• generics are not supported in the permits clause, afaik
• List shouldn't be in the permits list (same applies to other classes not generated by us)
• annotations are not supported in the permits clause, afaik

@martin-mfg how should I handle these? Just skip them?

[martin-mfg]

Did you intend to include these changes? If yes that's fine. Just want to check, since you didn't include this in your initial PR.

[alex-nt]

I just ran nix flake update as I wanted to make sure that it has the latest JDK11 build (got burned in the past in a minor jdk11 release). I can revert if that is preferred.

[martin-mfg]

It's fine, leave it as it is. :) No need to revert.

[martin-mfg]

how should I handle these? Just skip them?

Yes please. (Unless you have a better idea?)