Introduce a code-formatter plugin for repository code

[jxnu-liguobin]

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https://github.com/google/google-java-format

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[kobylynskyi]

@jxnu-liguobin , I don't think that we need to include it as part of your codegen.
That should be up to the client to use it or not.
What do you think?

[jxnu-liguobin]

It may not be described clearly. I mean that we need to unify the code style of the library, not the generated code.

[kobylynskyi]

Indeed, the following plugin can be used:
https://github.com/diffplug/spotless/tree/main/plugin-gradle#java

[jxnu-liguobin]

Yes, it's better