12:21 p.m.
Code level: 5.2.0.Final
I have a DRL file that includes a declared type:
package com.abclegal.rules.servicerequirements
declare TransgressionMetaData
attempt : ServiceAttempt
requirement : Requirement
end
The package loads the first time and its rules run without error. If I make
a change to the file and hot-deploy it (copy it to the server), the
ResourceChangeScanner picks up the file and KnowledgeAgent loads it, but
when any rule from that package subsequently fires, I get a
ClassCastException on the declared type:
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData
it appears the KnowledgeAgent is not replacing the existing (in working
memory) definition of the declared type, but instead is creating a new one
with a different hash code.
looks like a bug?
Full stack trace:
Caused by: RulesConsequenceException executing consequence for rule
"PHOTO_WHEN_SERVED: Photo must be taken if served." in
com.abclegal.rules.servicerequirements
[Error: drools.insert(new TransgressionMetaData($attempt,$req)):
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData]
[Near : {... @Modify with($attempt){ ....}]
^
[Line: 1, Column: 1]
java.lang.ClassCastException:
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData
Rules working memory:
Fact ServiceAttempt id: 17
at
com.abclegal.rules.utility.RulesConsequenceExceptionHandler.handleException(RulesConsequenceExceptionHandler.java:24)
at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:912)
at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:845)
at org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1056)
at
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:733)
at
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:699)
at
org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:218)
at
org.drools.impl.StatelessKnowledgeSessionImpl.execute(StatelessKnowledgeSessionImpl.java:305)
at
com.abclegal.rules.server.RulesServiceImpl.execute(RulesServiceImpl.java:378)
... 44 more
Caused by: [Error: drools.insert(new TransgressionMetaData($attempt,$req)):
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData]
[Near : {... @Modify with($attempt){ ....}]
^
[Line: 1, Column: 1]
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:409)
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.optimizeAccessor(ReflectiveAccessorOptimizer.java:140)
at
org.mvel2.optimizers.dynamic.DynamicOptimizer.optimizeAccessor(DynamicOptimizer.java:67)
at org.mvel2.ast.ASTNode.optimize(ASTNode.java:154)
at org.mvel2.ast.ASTNode.getReducedValueAccelerated(ASTNode.java:110)
at org.mvel2.MVELRuntime.execute(MVELRuntime.java:86)
at
org.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:122)
at
org.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:115)
at org.mvel2.MVEL.executeExpression(MVEL.java:928)
at org.drools.base.mvel.MVELConsequence.evaluate(MVELConsequence.java:105)
at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:906)
... 51 more
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.getMethod(ReflectiveAccessorOptimizer.java:1066)
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:338)
... 61 more
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
3:51 a.m.
This is a known bug: https://issues.jboss.org/browse/JBRULES-2962 Some
improvements were made in 5.3 and 5.4 but AFAIK, the issue still remains.
Could you please try using 5.4.SNAPSHOT ot beta1 to see if the error
persists?
Best Regards,
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Esteban Aliverti
- Developer @ http://www.plugtree.com
- Blog @ http://ilesteban.wordpress.com
On Mon, Jan 16, 2012 at 7:21 PM, lhorton <LHorton(a)abclegal.com> wrote:
Code level: 5.2.0.Final
I have a DRL file that includes a declared type:
package com.abclegal.rules.servicerequirements
declare TransgressionMetaData
attempt : ServiceAttempt
requirement : Requirement
end
The package loads the first time and its rules run without error. If I
make
a change to the file and hot-deploy it (copy it to the server), the
ResourceChangeScanner picks up the file and KnowledgeAgent loads it, but
when any rule from that package subsequently fires, I get a
ClassCastException on the declared type:
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData
it appears the KnowledgeAgent is not replacing the existing (in working
memory) definition of the declared type, but instead is creating a new one
with a different hash code.
looks like a bug?
Full stack trace:
Caused by: RulesConsequenceException executing consequence for rule
"PHOTO_WHEN_SERVED: Photo must be taken if served." in
com.abclegal.rules.servicerequirements
[Error: drools.insert(new TransgressionMetaData($attempt,$req)):
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData]
[Near : {... @Modify with($attempt){ ....}]
^
[Line: 1, Column: 1]
java.lang.ClassCastException:
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData
Rules working memory:
Fact ServiceAttempt id: 17
at
com.abclegal.rules.utility.RulesConsequenceExceptionHandler.handleException(RulesConsequenceExceptionHandler.java:24)
at
org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:912)
at
org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:845)
at
org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1056)
at
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:733)
at
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:699)
at
org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:218)
at
org.drools.impl.StatelessKnowledgeSessionImpl.execute(StatelessKnowledgeSessionImpl.java:305)
at
com.abclegal.rules.server.RulesServiceImpl.execute(RulesServiceImpl.java:378)
... 44 more
Caused by: [Error: drools.insert(new TransgressionMetaData($attempt,$req)):
com.abclegal.rules.servicerequirements.TransgressionMetaData cannot be cast
to com.abclegal.rules.servicerequirements.TransgressionMetaData]
[Near : {... @Modify with($attempt){ ....}]
^
[Line: 1, Column: 1]
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:409)
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.optimizeAccessor(ReflectiveAccessorOptimizer.java:140)
at
org.mvel2.optimizers.dynamic.DynamicOptimizer.optimizeAccessor(DynamicOptimizer.java:67)
at org.mvel2.ast.ASTNode.optimize(ASTNode.java:154)
at
org.mvel2.ast.ASTNode.getReducedValueAccelerated(ASTNode.java:110)
at org.mvel2.MVELRuntime.execute(MVELRuntime.java:86)
at
org.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:122)
at
org.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:115)
at org.mvel2.MVEL.executeExpression(MVEL.java:928)
at
org.drools.base.mvel.MVELConsequence.evaluate(MVELConsequence.java:105)
at
org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:906)
... 51 more
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.getMethod(ReflectiveAccessorOptimizer.java:1066)
at
org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:338)
... 61 more
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
_______________________________________________
rules-users mailing list
rules-users(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
11:39 a.m.
I tried this with 5.4 beta1 and I think the problem is still there. The
error I see when re-loading a drl that contains a declared type is:
DEBUG 2012-01-19 09:37:37,358 [com.abclegal.rules.server.RulesServiceImpl] -
BinaryResourceDiffProducerImpl: Couldn't handle
org.drools.rule.TypeDeclaration@2f084681. We must leave it in the new
Package.
I see this same message in 5.2 and in 5.4 beta1
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
4:22 a.m.
The problem is more complicated than it seems: imagine you
- load the DRL the first time
- create some instances of your clas
- load the DRL a second time
all the instances created so far would be "orphaned".
Likewise, all patterns include a type check: should that be updated?
We are still looking for an optimal policy. For now, my suggestion is to
include the declarations
in a different DRL (even better if you use a different package), keeping
them separate from
the rules that may have a different lifecycle.
Davide
( If this does not apply, please open a "zero-day" jira and force us to find
a solution :) )
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
10:33 p.m.
Thank you, Davide. This is not a critical bug for my shop so I don't wish to
force a JIRA when other Drools work might be more important.
My workaround so far is just to rename the declared class if I have to
hot-deploy, that way there are no conflicts.
I tried to separate the declared class from the drl but did not have
success. I tried putting the declaration into its own drl with a different
package name, but the drl file that used the declared class, even when
including an import for the package name with declared class name, did not
find the declared class. I have not had time to troubleshoot this. Have you
done it with success? We don't use Guvnor; instead we have drl and xls
files loaded with a change set.
No need to spend a lot of time on this, it is not critical for us, but if
you have any more insights I would be happy to hear them.
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
10:34 p.m.
I meant to say also, we use only Stateless knowledge sessions, so no worries
about existing orphaned facts. It is all new, each session
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
4:55 a.m.
In which order do you load the DRLs? Since resources are loaded one at a
time, the DRL with the declarations should be added to the knowledgebase
first.
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
4:24 p.m.
I was able to create a working unit test for the workaround of moving the
declared type out of the rules file and into a different package; but when I
deployed this change on my server, the files loaded ok the first time, but
again I ran into trouble when I would redeploy the base rules file. This
time I got an error when the knowledge agent tried to load the package:
WARN 2012-01-18 14:15:03,416 [com.abclegal.rules.server.RulesServiceImpl] -
KnowledgeAgent has KnowledgeBuilder errors object=Unable to resolve
ObjectType 'TransgressionMetaData' : [Rule name='Remedy Transgressions ']
Which looks like another symptom of the same bug. I will see if I can test
for the bug with 5.4 when I get a chance.
--
View this message in context:
http://drools.46999.n3.nabble.com/ClassCastException-when-KnowledgeAgent-...
Sent from the Drools: User forum mailing list archive at Nabble.com.
4695
days inactive
4698
days old
7 comments
3 participants
participants (3)
-
Davide Sottara -
Esteban Aliverti -
lhorton