"Illegal reflective access" warning should be addressed

[mschechter-bellese]

Describe the bug
Version 2.11 of the Maven plugin (available on Maven Central) generates the following working during formatting:

09:24:58.285 [INFO] --- fmt-maven-plugin:2.11:format (default) @ xxxxx ---
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.googlejavaformat.java.JavacTokens$CommentSavingTokenizer (file:/Users/xxxx/.m2/repository/com/google/googlejavaformat/google-java-format/1.10.0/google-java-format-1.10.0.jar) to field com.sun.tools.javac.parser.JavaTokenizer.reader
WARNING: Please consider reporting this to the maintainers of com.google.googlejavaformat.java.JavacTokens$CommentSavingTokenizer
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

To Reproduce
Execute the format goal

Expected behavior
The warning should not occur

Additional context
I have reverted to the 2.10 plugin release, and the issue no longer occurs. This is a valid workaround for my team, so we're not blocked. You're still using this version on master, there's still a potential issue in subsequent releases.

I've also created an issue in the google-java-format project, as this is most likely in their code.

[klaraward]

I recently learnt about the .mvn/jvm.config where you can add

--add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED --add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED

[youngm]

So, those arguments certainly work. However, it would be nice if we eventually don't not have to add them.

[klaraward]

See also #99

[danielnorberg]

These warnings are still issued for JDK 9 to 15, despite #140

[danielnorberg]

Closed by #150