PropertyExistsFunction blows up GeoServer shapefile usage on IBM JDK

Description

Trying to use a IBM specific tool (Java Lock Analyzer) I run GeoServer on an IBM jdk 6.0 and found out shapefiles were not loaded because of an issue locating the lentgh function. It turned out the function factory was blowing up on PropertyExistsFunction.equals with an NPE.
The attached patch cures the problem, I have no idea why this is not happenig on a Sun JDK.

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Unassigned

Reporter

codehaus

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Priority

Medium
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