getResource() returning null sporadically

I am loading an XSD file from the jar doing...

URL myurl = this.getClass().getResource("/com/test/sample.xsd);

During testing on a few occassions the program ran for a while then getResource() returned null. Not repeatable.

What other reaons besides the resouce not being found or permissions would cause getResource() return null?

Could this have something to do with low system memory? On one occassion the system was heavily loaded. The apps max memory was 512MB but it was using < 150MB.

[525 byte] By [hhalea] at [2007-11-27 11:59:03]