CASSANDRA-14572 Expose all table metrics in virtual tables

[Mmuzaf]

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The Cassandra Jira

[michaelsembwever]

can we not have this java file under src/java/ please.

like the test/anttasks/org/apache/cassandra/anttasks/ files, a separate directory structure would be nice (intuitive it's a separate compile and run classpath)

no good suggestions, maybe test/annotation-processor/src/ ?

[Mmuzaf]

While the SystemViewAnnotationProcessor reduces the need for boilerplate code for some additional model classes, it does add complexity to the build scripts. This is a trade-off that we need to agree on.

For me, keeping all the generated classes sounds slightly better than increasing the complexity of the build, as the build.xml is already quite large. Do you think it's better to remove the SystemViewAnnotationProcessor or is it better to keep it and move it to the path you've suggested?

The rationale is here, option #1 from here.
https://issues.apache.org/jira/browse/CASSANDRA-14572?focusedCommentId=17800171&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-17800171

[michaelsembwever]

I'm +0 towards not keeping the generated classes. And the build complexity can hopefully be all encapsulated in a separate .build/build-compile-annotations.xml file.

If it is kept, then keep it elsewhere than the main src/java/ please.

[Mmuzaf]

Ok, let's leave it as is for now. I moved it to test/annotation-processor, but we don't have a good place for it, as it's neither the tools nor the tests are suitable.