We should update Jena to its version 5 series. The latest Jena 5 version offers a multitude of improvements. However, the Apache Jena site states, "Jena5 requires Java 17, or a later version of Java."
Currently, OpenRefine requires Java 11. Upgrading to Java 17 (or even 21) should not be an issue since later Java runtime envs are generally backward compatible with earlier ones. I think we are "over the hump" with Java version issues since we have been packaging a Java 11 runtime for the Windows and Mac OSs.
Blockers for this will be any dependencies that absolutely requires a lower Java version. I don't see that as an issue since Java 17 (or 21) should be able to run any existing, lower version bytecode.
Requirement include:
Update Maven Jena version
Update Java runtime packaging to the selected late model Java version (17 or 21?).
I think we have a list somewhere(possibly here on the forum) with a collection of breaking changes we would like to do. This should probably go on that list.
I think this is a good candidate for that list. I realize there's no way of really knowing the extent to which bumping the minimum required version will break individual installations, but is there any data (even anecdotally) about which Java versions are still in use among OpenRefine users? I haven't seen any in the various user survey feedback blog posts and forum threads.