[jdom-interest] B-7's MANIFEST.MF and newer versions of Xerces = PROBLEMS!!!

Jan C. Zawadzki jcz at geniesystems.com
Mon Sep 17 17:20:13 PDT 2001

Well, at least under Linux (RH 7.1 & Mandrake 8), both the Sun and IBM 
JDK's load the xerces.jar based on that entry.

On the whole I would argue that while it is nice to be able to have the 
standalone behaviour, JDOM is after all a library primarily, and this 
nicety can cause severe problems in core functionality.

I guess it wouldn't be too bad if the errors it triggered were obvious 
and easy to track down - but they are not.  As it stands right now the 
Linux JVM's appear to load xerces out of the blue - without an entry in 
the CLASSPATH, etc.  Unless you know about this JAR capability (which 
I'd guess most people aren't really aware of), you'll be reduced to 
scanning for static classloaders and such - as I did before a "grep" 
located the manifest entry.

All I'm saying is that it is not unlikely that people use an updated 
version of Xerces under Linux - and in general, that CLASSPATH order 
dependencies should be avoided.

To solve the problem of -jar jdom.jar doing something useful could we 
look at the URLClassLoader?  At least that way the behaviour is limited 
to actual JDOMAbout use...


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