Java on handhelds

Hello,
Does anyone out there use a Palm Pilot or HP Ipaq to write Java code on? Is
this even doable? If so, is it dreadfully slow and what handheld do you
recommend? I don't mean by this question whether java code could be written
for a handheld, but whether you can write code for a PC on your handheld,
instead of the other way around. I ask this because it could make life much
simpler for me if I could just buy one of these devices instead of lugging
around my 50 pound laptop.
Thank you for any input,
Simon


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