George Mandler wrote:
>I purchased some expensive software to help me in my graduate studies . The
>author said that is works fine in OS 9.2, but doesn't work in OSX because
>of Apple Java problems.
> ...
>[quoting developer] "... I've read that Apple
>eventually plans to incorporate the Java engine into ROM-resident code,
>which should speed things up considerably. The current bottleneck is in how
>Java interfaces with the Mac graphical display routines."
There are speed problems with some Java graphics on Mac OS X. Search the
archives for "graphics performance" if you want to read the history of
laments.
What you can do about it depends on exactly which OS version, which Java
version, and which video-card you have. Without knowing that info, I can
only describe general strategies.
If graphics performance is this app's particular bottleneck, J2SE 1.3 has
hardware-acceleration facilities built into it that are not present in J2SE
1.4 on Mac OS X. The 1.3-to-1.4 transition had a lot of differences "under
the hood", best summarized or explained in the initial 1.4 release notes:
<http://developer.apple.com/releasenotes/Java/java141/index.html>
The info on 1.3's hwaccel is here:
<http://developer.apple.com/releasenotes/Java/Java131MOSX10.2RN/hardwareaccel/index.html>
All release notes reachable here:
<http://developer.apple.com/releasenotes/Java/>
If the app works on 9.2, then it must be JDK 1.1 compatible. Therefore, it
can't be using any of the latest Java features like BufferedImage, etc.
from JDK 1.2 and higher. BufferedImage etc. can be notably faster than the
older-style 1.1 Images -- or not, depending on specific circumstances. But
if the app is 1.1-compatible, then you might benefit from 1.3.1's hwaccel,
assuming you have appropriate video hardware.
In any case, you should be able to profile the Java app on Mac OS X and
find out where the bottlenecks are. That would take some skill and effort
to perform, so I suggest starting with hwaccel of 1.3.1, if at all possible.
The ROM-resident Java engine seems bogus to me. In general, ROMs are
slower than the fastest SDRAMS, and have been for several years. Some time
ago Mac OS itself was changed so it copies ROM code into RAM, for the extra
speed. So putting Java into ROM would gain almost nothing in speed over
having it on disk, and incur a whole lot of extra production cost, as well
as being far less upgradeable (unless it was in flash or EEPROM, which are
even more expensive).
I wouldn't hold my breath for Java in Mac ROMs, at least until someone
writes a JVM using Open Firmware (basically, a Forth interpreter).
-- GG
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