[rules-users] [rules-dev] class loading problems with 5.3.0-Final and 5.4.0-SNAPSHOT

Tue Nov 15 12:49:34 EST 2011

Yes, that's pretty interesting, but it also means that the issue you're
experiencing is not related with my change.
It looks more related with the Drools CompositeClassLoader and (probably)
with how it interacts with the WSO2 ClassLoader, so I don't think I can
help that much with it.

Anyway if you send a bit more info on how to reproduce this issue (I don't
know WSO2 at all) I could try to figure out what is going wrong.

Mario

On Tue, Nov 15, 2011 at 6:40 PM, Mauricio Salatino <salaboy at gmail.com>wrote:

> Interesting,
> If I run the same code with the 5.4.0-SNAPSHOT patched version (commented
> and uncommitted lines in JavaDialect) I get the same error that I'm getting
> with 5.3.0.Final:
>
> Exception in thread "Thread-44" java.lang.ClassCircularityError:
> org/drools/spi/KnowledgeHelper
>  at java.lang.Class.forName0(Native Method)
> at java.lang.Class.forName(Class.java:247)
>  at
> org.drools.util.CompositeClassLoader$CachingLoader.load(CompositeClassLoader.java:262)
> at
> org.drools.util.CompositeClassLoader.loadClass(CompositeClassLoader.java:105)
>  at
> org.drools.rule.JavaDialectRuntimeData$PackageClassLoader.loadClass(JavaDialectRuntimeData.java:540)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>  at
> org.eclipse.core.runtime.internal.adaptor.ContextFinder.loadClass(ContextFinder.java:124)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>  at java.lang.Class.forName0(Native Method)
> at java.lang.Class.forName(Class.java:247)
>  at
> org.drools.util.CompositeClassLoader$CachingLoader.load(CompositeClassLoader.java:262)
> at
> org.drools.util.CompositeClassLoader.loadClass(CompositeClassLoader.java:105)
>  at
> org.drools.rule.JavaDialectRuntimeData$PackageClassLoader.loadClass(JavaDialectRuntimeData.java:540)
> at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>  at
> test.Rule_request_bed_3ef79db278164a0c83e4d5dee4930562DefaultConsequenceInvoker.evaluate(Rule_request_bed_3ef79db278164a0c83e4d5dee4930562DefaultConsequenceInvoker.java:16)
>  at
> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1091)
> at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1029)
>  at org.drools.common.DefaultAgenda.fireUntilHalt(DefaultAgenda.java:1229)
> at
> org.drools.common.AbstractWorkingMemory.fireUntilHalt(AbstractWorkingMemory.java:756)
>  at
> org.drools.common.AbstractWorkingMemory.fireUntilHalt(AbstractWorkingMemory.java:732)
> at
> org.drools.impl.StatefulKnowledgeSessionImpl.fireUntilHalt(StatefulKnowledgeSessionImpl.java:234)
>  at
> com.wordpress.salaboy.hospital.HospitalServiceImpl$1.run(HospitalServiceImpl.java:71)
>
> As you can see it's the same exception, but the stack trace looks a little
> bit different. The generated class contains a couple of UUIDs.
>
> Cheers
>
> On Tue, Nov 15, 2011 at 2:27 PM, Mauricio Salatino <salaboy at gmail.com>wrote:
>
>> Mario,
>> The same code with 5.3.0.Final gives me:
>>
>> Exception in thread "Thread-44" java.lang.ClassCircularityError:
>> org/drools/spi/KnowledgeHelper
>> at java.lang.Class.forName0(Native Method)
>>  at java.lang.Class.forName(Class.java:247)
>> at
>> org.drools.util.CompositeClassLoader$CachingLoader.load(CompositeClassLoader.java:262)
>>  at
>> org.drools.util.CompositeClassLoader.loadClass(CompositeClassLoader.java:105)
>> at
>> org.drools.rule.JavaDialectRuntimeData$PackageClassLoader.loadClass(JavaDialectRuntimeData.java:540)
>>  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>> at
>> org.eclipse.core.runtime.internal.adaptor.ContextFinder.loadClass(ContextFinder.java:124)
>>  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>> at java.lang.Class.forName0(Native Method)
>>  at java.lang.Class.forName(Class.java:247)
>> at
>> org.drools.util.CompositeClassLoader$CachingLoader.load(CompositeClassLoader.java:262)
>>  at
>> org.drools.util.CompositeClassLoader.loadClass(CompositeClassLoader.java:105)
>> at
>> org.drools.rule.JavaDialectRuntimeData$PackageClassLoader.loadClass(JavaDialectRuntimeData.java:540)
>>  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>> at test.Rule_request_bedDefaultConsequenceInvoker.evaluate(Unknown Source)
>>  at
>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1091)
>> at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1029)
>>  at
>> org.drools.common.DefaultAgenda.fireUntilHalt(DefaultAgenda.java:1229)
>> at
>> org.drools.common.AbstractWorkingMemory.fireUntilHalt(AbstractWorkingMemory.java:753)
>>  at
>> org.drools.common.AbstractWorkingMemory.fireUntilHalt(AbstractWorkingMemory.java:729)
>> at
>> org.drools.impl.StatefulKnowledgeSessionImpl.fireUntilHalt(StatefulKnowledgeSessionImpl.java:234)
>>  at
>> com.wordpress.salaboy.hospital.HospitalServiceImpl$1.run(HospitalServiceImpl.java:71)
>>
>> I will comment the lines that you mention and go back with my simple
>> project url and the version of WSO2 AS that I'm using.
>> The whole installation and configuration should take only 5 minutes + the
>> download time of WSO2 that is about 150mgs.
>> Thanks for the help!
>> Cheers
>>
>> On Tue, Nov 15, 2011 at 1:09 PM, Salaboy <salaboy at gmail.com> wrote:
>>
>>> Hi Mario thanks! Give me an hour and I will get back with more details!
>>>
>>>
>>> - CTO @ http://www.plugtree.com
>>> - MyJourney @ http://salaboy.wordpress.com
>>> - Co-Founder @ http://www.jbug.com.ar
>>> - Mauricio "Salaboy" Salatino -
>>>
>>> On 15/11/2011, at 12:47, Mario Fusco <mario.fusco at gmail.com> wrote:
>>>
>>> Mauricio,
>>>
>>> I am the author of that change, so maybe I can help.
>>>
>>> First of all it seems weird to me that both the 5.3.0-Final and the
>>> 5.4.0-SNAPSHOT fail in the same way. I suppose the exception thrown by the
>>> 5.3 should be at least slightly different because it uses a different
>>> implementation of the ConsequenceGenerator. If so could you please send
>>> also the exception you get with the 5.3?
>>>
>>> Moreover I honestly don't know what WSO2 is but I guess this issue could
>>> be related with some specific constraint in its ClassLoader. Could you give
>>> me some more info in order to allow me to reproduce the same problem? By
>>> the way, does it happens with any rules or do you have a specific use case
>>> that causes this problem?
>>>
>>> In the end I can give you a quick workaround, but you will have to
>>> change the Drools source and of course recompile it. If you can do that you
>>> have to go to the JavaDialect class:
>>>
>>>
>>> https://github.com/droolsjbpm/drools/blob/master/drools-compiler/src/main/java/org/drools/rule/builder/dialect/java/JavaDialect.java#L92
>>>
>>> comment all the lines using the new ASM*Builders (94, 98, 102, 106) and
>>> uncomment the lines for the corresponding Java*Builer (92, 96, 100, 104). I
>>> know this is not the ideal solution, but at least it will allow us to
>>> figure out if the problem is actually where I am supposing.
>>>
>>> I could easily implement a fallback mechanism that will use the old
>>> Builders if the new ones fail for some reason, but before to do that I'd
>>> like to understand what's going on. So it will be great if you could send
>>> be some more details to help me to figure out what's wrong.
>>>
>>> I hope this helps,
>>> Mario
>>>
>>> On Tue, Nov 15, 2011 at 4:14 PM, Mauricio Salatino <salaboy at gmail.com>wrote:
>>>
>>>> Hi guys,
>>>> I'm working here trying to find out a little problem that I'm having
>>>> with Drools 5.4.0-SNAPSHOT and 5.3.0-Final.
>>>> I'm using WSO2 container to deploy a very simple service and when a
>>>> rule gets activated the following exception appears (with 5.4.0-SNAPSHOT):
>>>>
>>>> Exception in thread "Thread-44" java.lang.ClassCircularityError:
>>>> org/drools/rule/builder/dialect/asm/ConsequenceGenerator
>>>> at java.lang.Class.forName0(Native Method)
>>>>  at java.lang.Class.forName(Class.java:247)
>>>> at
>>>> org.drools.util.CompositeClassLoader$CachingLoader.load(CompositeClassLoader.java:262)
>>>>  at
>>>> org.drools.util.CompositeClassLoader.loadClass(CompositeClassLoader.java:105)
>>>> at
>>>> org.drools.rule.JavaDialectRuntimeData$PackageClassLoader.loadClass(JavaDialectRuntimeData.java:540)
>>>>  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>>>> at
>>>> org.eclipse.core.runtime.internal.adaptor.ContextFinder.loadClass(ContextFinder.java:124)
>>>>  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>>>> at java.lang.Class.forName0(Native Method)
>>>>  at java.lang.Class.forName(Class.java:247)
>>>> at
>>>> org.drools.util.CompositeClassLoader$CachingLoader.load(CompositeClassLoader.java:262)
>>>>  at
>>>> org.drools.util.CompositeClassLoader.loadClass(CompositeClassLoader.java:105)
>>>> at
>>>> org.drools.rule.JavaDialectRuntimeData$PackageClassLoader.loadClass(JavaDialectRuntimeData.java:540)
>>>>  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
>>>> at
>>>> test.Rule_request_bed_ede4a687c29740c8bb9f13968941e6a1DefaultConsequenceInvoker.evaluate(Unknown
>>>> Source)
>>>>  at
>>>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1091)
>>>> at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1029)
>>>>  at
>>>> org.drools.common.DefaultAgenda.fireUntilHalt(DefaultAgenda.java:1229)
>>>> at
>>>> org.drools.common.AbstractWorkingMemory.fireUntilHalt(AbstractWorkingMemory.java:756)
>>>>  at
>>>> org.drools.common.AbstractWorkingMemory.fireUntilHalt(AbstractWorkingMemory.java:732)
>>>> at
>>>> org.drools.impl.StatefulKnowledgeSessionImpl.fireUntilHalt(StatefulKnowledgeSessionImpl.java:234)
>>>>  at
>>>> com.wordpress.salaboy.hospital.HospitalServiceImpl$1.run(HospitalServiceImpl.java:71)
>>>>
>>>> I'm worried to see that I don't have any problems with 5.1.1 but with
>>>> later version all throw similar issues.
>>>> I will be trying to solve this issue, but if someone has a clue about
>>>> what can be happening here, please let me know.
>>>>
>>>> I know that this can be a particular issue with WSO2, but it looks like
>>>> something has changed inside drools.
>>>>
>>>> Cheers
>>>>
>>>>
>>>> --
>>>>  - CTO @ http://www.plugtree.com
>>>>  - MyJourney @ http://salaboy.wordpress.com
>>>>  - Co-Founder @ http://www.jugargentina.org
>>>>  - Co-Founder @ http://www.jbug.com.ar
>>>>
>>>>  - Salatino "Salaboy" Mauricio -
>>>>
>>>>
>>>> _______________________________________________
>>>> rules-dev mailing list
>>>> rules-dev at lists.jboss.org
>>>> https://lists.jboss.org/mailman/listinfo/rules-dev
>>>>
>>>>
>>> _______________________________________________
>>> rules-dev mailing list
>>> rules-dev at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/rules-dev
>>>
>>>
>>
>>
>> --
>>  - CTO @ http://www.plugtree.com
>>  - MyJourney @ http://salaboy.wordpress.com
>>  - Co-Founder @ http://www.jugargentina.org
>>  - Co-Founder @ http://www.jbug.com.ar
>>
>>  - Salatino "Salaboy" Mauricio -
>>
>>
>
>
> --
>  - CTO @ http://www.plugtree.com
>  - MyJourney @ http://salaboy.wordpress.com
>  - Co-Founder @ http://www.jugargentina.org
>  - Co-Founder @ http://www.jbug.com.ar
>
>  - Salatino "Salaboy" Mauricio -
>
>
> _______________________________________________
> rules-dev mailing list
> rules-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-dev
>
>
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