Following this poll (please keep voting btw), I think it’s time to draw some preliminary conclusions.
First I was expecting a bit more participation, but hey, we did our best to promote it. As of today with 29 voters, it turns out that about half users have Java 21, whilst there are still a few irreducibles stuck with 8. The rest uses 17 basically.
This would be my suggestion for the next steps (please reply and give your own opinion):
Orekit 13.X should be the last series in Java 8
Next year, we should upgrade to Java 17 or 21. To decide which one I believe we should hold another poll in between.
I wonder if we should (or even could) make a distinction between the runtime version and the compilation version.
For example, could we have source code and binary version remain compatible with 1.8 for users benefits while requiring a more recent Java for building, so we can use updated maven plugins?
We could also do the following to give a bit more time to users:
Orekit 13.x in Java 8
Orekit 14.0 in Java 8 immediately followed by Orekit 15.0 in Java 17 or 21. The downside being that bug fixes for 14.x would have to be done in parallel for some time…
It is possible to keep the language level to 1.8 while using higher version for building but we would not be able to benefit from features and optimization of higher Java version.