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Re: [udig-devel] jai is driving me cray 
HI,
That's exactly what we do. JAI can be hellish if you're not careful.... :) 

Jesse


On Apr 5, 2007, at 3:05 AM, Andrea Antonello - HydroloGIS wrote:


Thanks Andrea, Jesse,
I now at least know the proper way to do things.

0) put "Eclipse-BuddyPolicy: ext" in the manifest file
1) have jai installed in your java installation
2) whenever you supply a product to someone, supply also the jre of that 
java installation

That way for me it works nice and clean.
Did I get it right?

Ciao
Andrea




Jesse Eichar probaly wrote:
We always use the JAI that is installed in the ext directory. Where is this code being called from? Every plugin that uses JAI must add the line: 

Eclipse-BuddyPolicy: ext

In your manifest.mf file.
This states that the extensions in the JVM's lib/ext directory will be available on the classpath of that plugin. It could be that the method 
you are using is getting the File from the wrong classloader (the lib
one perhaps).
If you can give me some details about what you're doing I might be able 
to come up with a better answer.

Jesse


On Apr 4, 2007, at 6:28 AM, Andrea Antonello wrote:


Hi folks, I have (once again) a problem with jai:

java.lang.ClassCastException:
com.sun.media.jai.imageioimpl.ImageReadWriteSpi
    at
javax.media.jai.OperationRegistry.registerServices (OperationRegistry.java:2047) 

    at
javax.media.jai.ThreadSafeOperationRegistry.registerServices (ThreadSafeOperationRegistry.java:612) 

    at
javax.media.jai.OperationRegistry.initializeRegistry (OperationRegistry.java:365) 

    at javax.media.jai.JAI.<clinit>(JAI.java:560)


So what is the best practice?
The best practice is the harder to attain. You should have the JAI jars installed directly into your JDK, and don't have them anywhere in the 
classpath. Otherwise you're bound to issues as soon as a damned
classloader does not play exactly by the Sun rules. Sigh...
Yes, but that gives me big troubles when I have to export a product. I usually somehow have some reference in it and when not it fails because there is some dependency. I agree with the fact that this is a problem of mine and that I should know a bit better how exactly to do a clean and proper export of an eclipse product, but things would be much easier 
if the lars could be put in the classpath and the .so in the library
path :)


The issue is that JAI is packaged as an extension, and it's sealed.
We still haven't tried hacking the official jars and remove the sealing markers, but that would be an interesting test too (that is, to check if this way JAI can be handled both in the JDK/JRE and in the classpath). 

Oh, that is something I didn't know, the sealing thing I mean. I
remember there was also a download version for classpath use. Hmmm... 
I'll have to check.

Thanks for the informations,
Ciao
Andrea





_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
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--
______________________________________________________________________ ______ 
HydroloGIS - Environmental Safety Modelling
www.hydrologis.com

Andrea Antonello
Environmental Engineer
mobile:  +393288497722

"Let it be as much a great honour to take as to give learning,
if you want to be called wise."
Skuggsja' - The King's mirror - 1240 Reykjavik
______________________________________________________________________ ______ 



_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel

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