Too strict Java 21 check during preinst. Will also end up different from addons version, possibly failing fallback.

[olemr]

b936801#diff-c68a17347fa07d05676738879da006c8ce6602ed466304e27f1d5fd6be6f6e6fR64

Prior to 5.0.0 release, the preinst just issued a warning, but did not abort the script.
With the release version however, it does, and leaves the openhab installation on the previous version while happily installing the addons with the new version.

The Java version check should be done during openhab runtime, and not during install time.
When using sdkman for installing Java, sudo java -version and java -version does not necessary see the same version.
See https://community.openhab.org/t/5-0-0-m1-1-openhab-service-not-picking-up-java-21-installed-using-sdkman-but-17-instead/163640/4?u=omr for details, where the Java version in handled be systemd.

I suggest removing the exit 1 from the script, so that install behaviour is similar to the 5.0.0 Mx releases, or do the whole check during openhab runtime startup as not all Java environments are the same.

[BClark09]

Ah yes, issues with less common setups is what I was afraid of in #235 and #236. (CC @florian-h05, @holgerfriedrich)

There are two parts of this which need to be addressed differently.

leaves the openhab installation on the previous version while happily installing the addons with the new version.

This is unacceptable and the least that we need to add the same behavior in the addons package. This is my fault - I had overlooked this behaviour in the previous discussions.

I suggest removing the exit 1 from the script, so that install behaviour is similar to the 5.0.0 Mx releases,

I would oblige as this would be my preferred behaviour, but this repo is serving also other requirements and @openhab/openhabian-maintainers have asked for strict Java control to be handled in this repo. Which is fair even for non-openhabian users - openHAB should not be allowed to break because it has been upgraded to an incompatible version.

[mstormi]

add the same Java check to the addons pkginst?