Hum. i also thought that.
anyways i am not much worry about it as long as it is not gona come in my way.
and i am not going back to work with java again (as photoshop is the new frend).
So who cares about a single file extantion which you have nothing to do with.
Again thanx for your efforts :)
The easiest way is by directly editing the file associations in the registry. Open an elevated regedit, go to HKEY_CLASSES_ROOT\.jar (the last key is a point plus the extension) and delete it. It completely blows up the association and makes the file type unknown again.
You may need to restart explorer/log off/reboot to see the change.
An alternative way is to use some program to edit the file associations for you. A good option is FileTypesMan - Alternative to 'File Types' manager of Windows
Unfortunately, the screen for touching associations in a nicer way was removed in Vista, so you have to do workarounds.
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