[XERCESJ-1080] XSAttributeUseImpl.getConstraintValue() might cause NPE

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.6.2
• Fix Version/s: 2.9.1
• Environment: Xerces2-J CVS HEAD (May 12, 2005)
• Assignee: Michael Glavassevich
• Reporter: Kurt Riede
• Created: 13/May/05 03:50
• Updated: 17/Sep/07 02:16
• Resolved: 11/Jun/07 02:06

Description

In case of error "a-props-correct.2" (Invalid value constraint value '%1' in attribute '%2'.), attribute fDefault or fDefault.actualValue might be null and the code might result in a NPE.

How to reproduce: Example from xml schema test suite:
msxsdtest\attribute\attP006.xsd

In my case, when anlysing invalid schema files (as good as possible), it is important not to have this exception, so I'm working with my own patched version of Xerces2-J. It would be nice if you would fix this somewhen.

My fix is quite simple: just check on null:

Old:
return getConstraintType() == XSConstants.VC_NONE ?
null :
fDefault.actualValue.toString();

New:
return getConstraintType() == XSConstants.VC_NONE ? null :
(fDefault == null ? null :
(fDefault.actualValue == null ? null :
(fDefault.actualValue.toString())));