[FEATURE] [Java] Add "additionalModelTypeAnnotations" to enable using Lombok

[keks42]

Why do we need this improvement?

In our project we use lombok, specifically @lombok.Builder for models. The openapi-generator for spring has an option to set Annotations for model classes ("additionalModelTypeAnnotations"). [1]

It would be helpful to have such an opportunity for async api model generation as well.

[1] https://openapi-generator.tech/docs/generators/spring/

How will this change help?

With this featuer we would be able to use Lombok consistently.

Screenshots

No response

How could it be implemented/designed?

A parameter could be added ("javaClassAnnotations" would be a better name in the context of this project) that takes a String which is copied into every java class just in front of the line "public class...".

Default should be an empty string which makes it backwards-compatible.

🚧 Breaking changes

No

👀 Have you checked for similar open issues?

• I checked and didn't find a similar issue

🏢 Have you read the Contributing Guidelines?

• I have read the Contributing Guidelines

Are you willing to work on this issue?

Yes I am willing to submit a PR, but as I don't have a lot of time, feel free to work on it!

[github-actions]

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[jonaslagoni]

@keks42 if you want others to pick this issue up, I would suggest to add concrete output and the new output you are looking for 🙂

But it sounds like something presets can solve and happy to accept a PR ✌️