How to run google-java-format from Bazel?

先从 issue 中的 Bazel 和 pre-commit 上下文入手，然后检查 google-java-format 的 Main#format(String... args) 以及提议的 GoogleJavaFormatTest。完成标准是提供一个有文档记录且可复现的 Bazel 工作流，对已更改的 Java 文件运行 formatter，并定义预期的 build 行为。

I would like to run google-java-format in an (open source) project which uses Bazel as build system.

I currently have it set up using https://github.com/dustinsand/pre-commit-jvm (with https://pre-commit.com) but it strikes me as "odd" having to install https://get-coursier.io and relying on dustinsand/pre-commit-jvm when it should be possible to "just" have a (Maven) dependency on this in Bazel and "run it" - I'm just not entirely sure HOW one would be run a Java based tool like this one from Bazel...

... I have briefly explored something like what this post on bazel-discuss may have been after, and started to write my own GoogleJavaFormatTest using this project's API, but it doesn't seem to be intended to used like that (UsageException is package local only, even though Main#format(String... args) throws UsageException) - and integrated this as a b test //... is perhaps that's the wrong way to go about this anyway?

How would one best run google-java-format from Bazel? You would want it "run whenever any *.java changed", and one would want it to fail the build if the formatting was wrong - but re-write (correct) the source files. Is this possible with Bazel? How does one even "run a main() method from a dependency" for something like this?

@cushon perhaps you have some wise guidance?