[Java] Build memory-netty as a JPMS module

[jduo]

Describe the enhancement requested

This depends on apache/arrow#38998.

Build memory-netty as a JPMS module.

This change requires patching Netty's public module since we add classes to exposed packages and call package-private functions.

This requires users to add a patch-module command to their java invocation. It is somewhat inconvenient because it needs to reference one of our delivered JAR filenames (which vary by location and version)

Component(s)

Java

[dragonsahead]

Hi @jduo, maybe I’m mistaken, but is this the only missing item for #151?

Thanks!

[jduo]

Hi @jduo, maybe I’m mistaken, but is this the only missing item for #151?

Thanks!

Yes, and we do not plan to complete the netty piece due to user inconvenience.

[dragonsahead]

Thanks for the super quick answer. The reason I’m asking this is because it seems that the snowflake driver needs this dependency upgraded to support Java > 16. If this is not going to happen then I guess that the snowflake team is stuck?

[Sineaggi]

add classes to exposed packages and call package-private functions.

What classes are added and which package-private functions are called? If this functionality is required, should there be a conversation with netty wrt getting those packages opened?

[jduo]

All of the content in arrow-netty-buffer-patch either depends on Netty internals or depends on classes that is depend on Netty internals.

I think the most prevalent was Buffer.

This work seems to have been used as a way of optimizing Flight/gRPC integration.

[grepwood]

What are the functions in question? Which part of Arrow is affected? I'm interested in this issue