Absolutely the same, except that the Java system purports to be more security-aware.
Moreover, the original portable Pascal compiler by N. Wirth was done the same way, so the UCSD system wasn't the first, by a long shot, but it was pretty popular on Apples for a time. But it was basically just a copy of Wirth's original portable Pascal kit. (BTW, I still have a copy of the Pascal P-Machine spec from ETH Zurich!)
The only thing UCSD Pascal lacked, and the only thing that Java lacks, is a hardware implementation. It puzzles me: all the complaints about Java's speed, or lack of it, could easily be fixed by a hardware implementation of the virtual machine--a plug-in board, say--but I never hear anyone asking for it or proposing to do it. Odd.
Is anyone old enough to remember the Burroughs B-5500? The HP 9000? These were stack machines that implemented Algol semantics in hardware.
Charles Hethcoat
>>> Alan D Corre <corre@alpha1.csd.uwm.edu> 00-05-21 11:21:06 PM >>>
In article <200005171922.MAA09657@baskerville.CS.Arizona.EDU> Cary Coutant
<cary@cup.hp.com> writes:
>
>At the time, I was just copying the idea of a bytecode interpreter from
>the Pascal p-system. Little did I realize that Sun had yet to "invent"
>bytecode!
This prompts me to ask a question that has been bothering me for some time,
and to which I would appreciate a reply that is not overly technical. I used
Apple Pascal what seems like eons ago. It was a really nice system, invented
by Ken Bowles, if I remember correctly. My question is, why is there so much
fuss about Java working across different platforms? Was not the p-system a
"virtual machine" which could function in just that way?