java.lang.NullPointerException
	at org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.getRecord(BtreeDatabase.java:1013)
	at org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.getIfExists(BtreeDatabase.java:762)
	at org.netbeans.mdr.persistence.btreeimpl.btreestorage.BtreeDatabase.getIfExists(BtreeDatabase.java:741)
	at org.netbeans.mdr.storagemodel.MdrStorage.getObject(MdrStorage.java:697)
	at org.netbeans.mdr.handlers.BaseObjectHandler._getDelegate(BaseObjectHandler.java:351)
	at org.netbeans.mdr.handlers.InstanceHandler.getInstanceDelegate(InstanceHandler.java:48)
	at org.netbeans.mdr.handlers.InstanceHandler._handleGet(InstanceHandler.java:193)
	at org.netbeans.jmi.javamodel.Resource$Impl.getName(Unknown Source)
	at org.netbeans.modules.javacore.jmiimpl.javamodel.ResourceImpl.getStatus(ResourceImpl.java:334)
	at org.netbeans.jmi.javamodel.Resource$Impl.getStatus(Unknown Source)
	at org.netbeans.modules.java.bridge.SourceElementImpl.checkWritable(SourceElementImpl.java:321)
	at org.netbeans.modules.java.bridge.MemberElementImpl.checkWritable(MemberElementImpl.java:158)
	at org.netbeans.modules.java.bridge.ClassElementImpl.checkWritable(ClassElementImpl.java:628)
	at org.netbeans.modules.java.bridge.ClassElementImpl.setSuperclass(ClassElementImpl.java:252)
	at org.openide.src.ClassElement.setSuperclass(ClassElement.java:282)
	at org.netbeans.test.java.sourceexception.ClassChanged.ClassChanged.go(ClassChanged.java:82)