It's not about an admin being *capable* of doing it, it's the impact that an upgrade has on the existing hardware and software system(s).
What exactly would be the impact? All my upgrades have been completely painless. In fact, JDK 5 is better in performance than JDK 1.4, so HW upgrades should not be needed. Switching to a new version of JSPWiki is probably a greater strain on the computer than switching to a new JDK.
All problems that I have encountered were due to using pre-release JDK 5 systems, where some instability ensued. However, now that JDK 5 has been out for 3.5 years (let me repeat that: 3.5 *years*), I haven't encountered any problems with it. It's stabler, faster and generally nicer (esp. thanks to jconsole, which is a very nice tool for keeping track on what exactly your JVM is doing, and how to tweak it.)
What I do know is that a lot of admins are lazy or bad, and don't want to touch an existing system because they don't really know what they are doing. (Nobody on this list is luckily in that group.) Frankly, I would need to be paid a lot of money to do these lazy bastard's jobs for them. These people are happy with the old version of JSPWiki, and, if they want to, they can go through the upgrade cycle for a newer version, if they really need the services.
This is open source. If there is an incentive for someone to start a) supporting JDK 1.4 or b) supporting old versions, they are entirely free to do so. I would certainly welcome such an effort, but personally, I am not interested in it so much. The evidence suggests that our userbase is not very highly dependent on 1.4. I am going to post a short questionnaire to the user list to check for opinions.
But we, the developers, need to keep our codebase clean, reduce errors, and also work on new stuff to keep this interesting for us. JDK 5 and Stripes offer us good tools for this kind of stuff, and should also make life easier for admins as well in the long run. Therefore, I don't much see an alternative for us for 2008.
We could also offer a JDK 1.4 compatibility pack using the retrotranslator. It would not be complicated to add in the build files.
/Janne
