[Calimero3] Support issue

[holgerfriedrich]

Hi @bmalinowsky, many thanks for releasing Milestone 1!

I open this issue to collect feedback. Feel free to close it or leave it open for user feedback.

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First feedback from openHAB KNX binding: I had already prepared a build form 3.0-SNAPSHOT before and now just upgraded from 2.6. to 3.0-M1.
openhab/openhab-addons#18256

My mid-sized KNX installation now runs on M1.
It seems to work without issues. 🥳I will report any problems here.

Thanks a lot.

@bmalinowsky Can you already give an advice if M1 is ready for use in production? Should we better wait for next releases?

[bmalinowsky]

@holgerfriedrich M1 got tested the same as any other release, and there were not really changes recently on that branch, besides a few fixes. (The wait was also caused because of gradle/gradle#35521.)

So it is intended to be used 😀

In particular, it is a milestone for the following reasons:

• adoption of namespace changes, without too many other worries
• still uses Java 17, going forward will at least require JDK 21
• still has Maven build setup (I maintained both Gradle and Maven for a long time, which got tedious; I will only use Gradle onwards)

So it doesn't include other changes implemented on master (maybe will be another milestone)

• require >= JDK 21
• scheduler uses only virtual threads (there were a few openjdk bug reports wrt VTs & pinning issues during class-loading)
• auto-config for GraalVM native image (uses GraalVM 25)

For completeness: changes happen in other parts than the core repo. The only change noteworthy in calimero-core in practice I think is Unix domain socket support, which is nice when running a local (containerized) software knx server.

[holgerfriedrich]

Thanks for explaining the context., this is good to know!

In openHAB, we use calimero-core and calimero-device on Java 21.

With the transition to gradle, will you still support publishing to a local Maven cache, e.g. via the maven-publish-plugin? We are building with Maven and I tend to try out new Calimero features before they appear on Maven Central.... :-)

[bmalinowsky]

It's ./gradlew publishToMavenLocal (gradlew.bat on Windows). You don't need to manually install Gradle for this.

You can see all build tasks using ./gradlew tasks.

The whole v2.6 train was built and released using Gradle, so there shouldn't be too many issues. Anyway, if there are any problems, please get back to me.