I've just tried upgrading from Drools 5.3.0-CR1 from the beta and I've hit a
regression.
JBoss seems to have been down for most of today so I haven't been able to raise a Jira
for it.
In our model we have Facts which contain fields of java.lang.class, we then have a rule
which checks that they aren't null.
Eg
Fact { Class<Object> classField}
Rule "xyz"
When
Fact(classField != null)
Then
...
End
This is giving the following exception
Caused by: java.lang.ClassCastException: org.drools.base.field.ObjectFieldImpl cannot be
cast to org.drools.base.field.ClassFieldImpl
at
org.drools.base.evaluators.EqualityEvaluatorsDefinition$ClassEqualEvaluator.evaluate(EqualityEvaluatorsDefinition.java:1772)
at
org.drools.rule.LiteralRestriction.isAllowed(LiteralRestriction.java:87)
at
org.drools.rule.LiteralConstraint.isAllowed(LiteralConstraint.java:109)
at org.drools.reteoo.AlphaNode.assertObject(AlphaNode.java:130)
at
org.drools.reteoo.CompositeObjectSinkAdapter.doPropagateAssertObject(CompositeObjectSinkAdapter.java:451)
at
org.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject(CompositeObjectSinkAdapter.java:369)
at org.drools.reteoo.AlphaNode.assertObject(AlphaNode.java:134)
at
org.drools.reteoo.CompositeObjectSinkAdapter.doPropagateAssertObject(CompositeObjectSinkAdapter.java:451)
at
org.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject(CompositeObjectSinkAdapter.java:379)
at org.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java:204)
at org.drools.reteoo.EntryPointNode.assertObject(EntryPointNode.java:244)
at org.drools.common.NamedEntryPoint.insert(NamedEntryPoint.java:330)
at org.drools.common.NamedEntryPoint.insert(NamedEntryPoint.java:291)
at
org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:882)
at
org.drools.base.DefaultKnowledgeHelper.insert(DefaultKnowledgeHelper.java:180)
... 149 more
Wrapping the classField != null within an eval appears to be a work around.
This is in the suspect method:
public boolean evaluate(InternalWorkingMemory workingMemory,
final InternalReadAccessor extractor,
final Object object1, final FieldValue object2) {
Object value1 = extractor.getValue( workingMemory, object1 );
Object value2 = object2.getValue();
if ( value2 == null ) {
ClassFieldImpl classField = (ClassFieldImpl) object2;
value2 = classField.resolve( workingMemory );
}
return comparator.equals( value1, value2 );
}
I think the if statement just needs an instanceof check as well or some other way to track
the fact that null may be a valid value to be comparing with!
Thomas
________________________________
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received
this message in error, please immediately notify the postmaster(a)nds.com and delete it from
your system as well as any copies. The content of e-mails as well as traffic data may be
monitored by NDS for employment and security purposes. To protect the environment please
do not print this e-mail unless necessary.
NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United
Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603
8808 40-00
**************************************************************************************