There's a reason this is probably the only successful Java-based game ever.
Really, really untrue in my eyes. I'm not going to point out a bunch of successful Java games but every single Android game is coded in Java, all of the Android applications go through android's Dalvik virtual machine for runtime.
But I'm sure there has also be plenty of successful Java games other than Minecraft. Runescape is one of the first games that comes to mind, although it may not be the best example it is sure as hell extremely successful. The Dan Ball games, like the powder toy, are also coded in Java however they're not really
game games, more of sandboxes or tools.
Edit: Oh! And Puzzle Pirates is in Java, if I recall correctly. This was also pretty successful.