Nabble - Drools - Java Rules Engine

Re: invalid rule package

2008-09-07T03:35:35Z

ok. found the error.

i added a line which should execute a function wtih no entries in conditions . this should set a default value. any idea how to do this?

----- Original Message -----

From: Sascha.Janz@...

To: rules-users@...

Sent: Sunday, September 07, 2008 10:12 AM

Subject: [rules-users] invalid rule package

I'm a member of the drools mailinglist, so please answer me

am using jbpm with drools. my rules are defined in an excel sheet.

where must i install the class referenced in the excel sheet?

org.drools.rule.InvalidRulePackage: Rule Compilation error

formular(my class) cannot be resolved

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From forum: drools - user

invalid rule package

2008-09-07T01:12:34Z

I'm a member of the drools mailinglist, so please answer me

am using jbpm with drools. my rules are defined in an excel sheet.

where must i install the class referenced in the excel sheet?

org.drools.rule.InvalidRulePackage: Rule Compilation error

formular(my class) cannot be resolved

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From forum: drools - user

Drools eval condition element throws ClassNotFoundException

2008-09-07T01:03:27Z

HI,

Am getting the following exception when I tried calling fireAllRules(), I have also attached the Drool file with this post

Caused by: java.io.IOException: No ClassLoaders found for: BP_RL_144.Rule_Rule_0_0Eval0Invoker
at org.jboss.serial.classmetamodel.ClassMetamodelFactory.getClassMetaData(ClassMetamodelFactory.java:332)
at org.jboss.serial.classmetamodel.StreamingClass.readStream(StreamingClass.java:72)
at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.readObjectDescriptionFromStreaming(ObjectDescriptorFactory.java:381)
at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.objectFromDescription(ObjectDescriptorFactory.java:82)
at org.jboss.serial.objectmetamodel.DataContainer$DataContainerInput.readObject(DataContainer.java:845)
at org.jboss.serial.persister.RegularObjectPersister.readSlotWithFields(RegularObjectPersister.java:353)
at org.jboss.serial.persister.RegularObjectPersister.defaultRead(RegularObjectPersister.java:273)
at org.jboss.serial.persister.RegularObjectPersister.readData(RegularObjectPersister.java:241)
at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.readObjectDescriptionFromStreaming(ObjectDescriptorFactory.java:412)
at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.objectFromDescription(ObjectDescriptorFactory.java:82)
at org.jboss.serial.objectmetamodel.DataContainer$DataContainerInput.readObject(DataContainer.java:845)
at org.jboss.serial.persister.ObjectInputStreamProxy.readObjectOverride(ObjectInputStreamProxy.java:68)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:333)
at java.util.ArrayList.readObject(ArrayList.java:587)
... 134 more
Caused by: java.lang.ClassNotFoundException: No ClassLoaders found for: BP_RL_144.Rule_Rule_0_0Eval0Invoker
at org.jboss.mx.loading.LoadMgr3.beginLoadTask(LoadMgr3.java:212)
at org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:514)
at org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:408)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:242)
at org.jboss.serial.classmetamodel.ClassMetamodelFactory.resolveClassByName(ClassMetamodelFactory.java:274)
at org.jboss.serial.classmetamodel.ClassMetamodelFactory.getClassMetaData(ClassMetamodelFactory.java:289)
... 147 more

Please help me to resolve this issueBP_RL_FIRST.drl

From forum: drools - user

Returned mail: Data format error

2008-09-06T17:20:25Z

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From forum: drools - user

RE: Help with syntax for detecting when an object exists, none of whose children match a pattern

2008-09-06T00:12:32Z

Help with syntax for detecting when an object exists, none of whose children match a pattern

I am a bit of a newbie myself, but I assume the following would work:

When

$p: ParentFactObject()

$c: childFactObject(TestMe==false) from $p.ChildFactObjectList

Then

//do something

End

Another way is to simply assert the ChildFactObjectList as separate facts into the working memory and then pattern match just them.

Cheers,

Vikrant

From: rules-users-bounces@... [mailto:rules-users-bounces@...] On Behalf Of Tom.E.Murphy@...
Sent: Saturday, September 06, 2008 2:49 AM
To: rules-users@...
Subject: [rules-users] Help with syntax for detecting when an object exists, none of whose children match a pattern

As a newbie to Drools (using v4.0.7), I’m struggling a bit with the right way to express the following concept

I have a ParentFactObject with an array of ChildFactObjects.

The ChildFactObjects have a boolean attribute “TestMe”

I want to pattern match all ParentFactObjects for whom all ChildFactObjects have false for TestMe

Here’s what I’ve tried:

rule "NoTestChildren"

when

$parentFactObject : ParentFactObject // parent exists

(

)

not ChildFactObject // no child exists that has TestMe true

(

TestMe == true

) from $parentFactObject.childFactObjects

then

log("Rule NoTestChildren fired.");

end

I get the following:

org.drools.rule.InvalidRulePackage: [66,4]: unknown:66:4 mismatched token: [@1085,4469:4472='from',<38>,66:4]; expecting type THEN

Also tried this:

rule " NoTestChildren "

when

$parentFactObject : Borrower // parent exists

(

)

forall ($childFactObject : ChildFactObject // no child exists that has TestMe true

(

TestMe == true

) )from $parentFactObject. childFactObjects

then

log("Rule NoTestChildren fired.");

end

I’ve tried a series of variations with similar results.

Can anyone provide any guidance on how to do this?

Thanks in advance.

Tom Murphy

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From forum: drools - user

Facing an issue with Drools Query

2008-09-06T00:10:10Z

Hi,

I am facing an issue with Drools Query.

Our application serializes working memory after its each execution, to save the rule engine state.

Our rule base contains a Query along with other rules:

query "GetFactsByValue" ( String $value )
Facts : DataObject( stringValue == $value )
end

With this query present in Rule Base, if I insert more then 900 instances of DataObject & then try to serialize the working memory... serialization fails with bellow error:

java.lang.StackOverflowError
at java.io.ObjectStreamClass.processQueue(Unknown Source)
at java.io.ObjectStreamClass.lookup(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

But if I remove the query from rule base, I can insert more then 60,000 objects & then serialize WM without any problem.

Not sure if this is a bug in Query feature or problem in the way I have written the Query. I have attached test files.

We are using few more queries in our RuleBase like:

query "GetAllFacts" ( )
    Fact : DataObject( )
end

query "GetFactsByDate" ( Calendar $startDate, Calendar $endDate )
    Fact : DataObject( startDate >= $startDate, endDate <= $endDate )
end

query "GetFactsByParamIdTimeRange" ( ArrayList $paramIDs, Calendar $startDate, Calendar $endDate )
    Facts : DataObject( paramID memberOf $paramIDs, startDate >= $startDate, endDate <= $endDate )
end

Not sure if they also may fail in some special scenarios. Atleast last 3 Queries we are planning to use in our production. Is it ok to use those?

Execution Environment:

OS: Windows/ Solaris

Drools 4.0.7

jre1.5.0_09

Thanks

Siddhartha

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TestQuery.zip (3K) Download Attachment

From forum: drools - user

Help with syntax for detecting when an object exists, none of whose children match a pattern

2008-09-05T14:19:21Z

Help with syntax for detecting when an object exists, none of whose children match a pattern

As a newbie to Drools (using v4.0.7), I’m struggling a bit with the right way to express the following concept

I have a ParentFactObject with an array of ChildFactObjects.

The ChildFactObjects have a boolean attribute “TestMe”

I want to pattern match all ParentFactObjects for whom all ChildFactObjects have false for TestMe

Here’s what I’ve tried:

rule "NoTestChildren"

when

$parentFactObject : ParentFactObject // parent exists

(

)

not ChildFactObject // no child exists that has TestMe true

(

TestMe == true

) from $parentFactObject.childFactObjects

then

log("Rule NoTestChildren fired.");

end

I get the following:

org.drools.rule.InvalidRulePackage: [66,4]: unknown:66:4 mismatched token: [@1085,4469:4472='from',<38>,66:4]; expecting type THEN

Also tried this:

rule " NoTestChildren "

when

$parentFactObject : Borrower // parent exists

(

)

forall ($childFactObject : ChildFactObject // no child exists that has TestMe true

(

TestMe == true

) )from $parentFactObject. childFactObjects

then

log("Rule NoTestChildren fired.");

end

I’ve tried a series of variations with similar results.

Can anyone provide any guidance on how to do this?

Thanks in advance.

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From forum: drools - user

RE: Drools, Performance issues on 4.0.7 Vs 2.5

2008-09-05T12:46:28Z

Thanks Edson. Is there any example to rewrite the rule without rule?

From: rules-users-bounces@... [mailto:rules-users-bounces@...] On Behalf Of Edson Tirelli
Sent: Friday, September 05, 2008 2:59 PM
To: Rules Users List
Subject: Re: [rules-users] Drools, Performance issues on 4.0.7 Vs 2.5

   Start by eliminating the evals and writing your constraints properly inside the patterns. Drools 3+ is orders of magnitude faster than Drools 2.x, but you need to leverage its power in your rules. Please read the manual as the version 3 was a completely rewrite of version 2. Version 4 is an improvement over 3.

   As an example, look at this: http://blog.athico.com/2006/11/rush-hour-and-content-based-routing.html

   []s
   Edson

2008/9/5 Rout, Sushanta (ThoughtMill) <Sushanta.Rout@...>

We were using Drools 2.5 version earlier. Now we have switched to drools
4.0.7. But we see significant issues with performance like drools 4.0.7
is three times slower than 2.5 . Has anybody encountered the issue?

Here is a sample of the rule, we have some more similar to this.
rule "test"
dialect "java"
activation-group "group1"
when
$croNumberDetailsRequest : CRONumberDetailsRequest()
$resdirectPhoneNumber : ResdirectPhoneNumber()
eval($resdirectPhoneNumber.getType().getId() == 5 &&

$resdirectPhoneNumber.isValidForBrand($croNumberDetailsRequest.getBrand(
)) &&
$croNumberDetailsRequest.getRegion() != null &&

$resdirectPhoneNumber.isValidRegion($croNumberDetailsRequest.getRegion()
) &&
$croNumberDetailsRequest.getLocale() != null &&

$resdirectPhoneNumber.isValidForLocaleId($croNumberDetailsRequest.getLoc
ale()) &&

$resdirectPhoneNumber.isValidSlot($croNumberDetailsRequest.getSlot()));

then
ResultList.add($resdirectPhoneNumber);
end

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--
Edson Tirelli
JBoss Drools Core Development
JBoss, a division of Red Hat @ www.jboss.com

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From forum: drools - user

Re: Drools, Performance issues on 4.0.7 Vs 2.5

2008-09-05T11:59:08Z

2008/9/5 Rout, Sushanta (ThoughtMill) <Sushanta.Rout@...>

We were using Drools 2.5 version earlier. Now we have switched to drools
4.0.7. But we see significant issues with performance like drools 4.0.7
is three times slower than 2.5 . Has anybody encountered the issue?

Here is a sample of the rule, we have some more similar to this.
rule "test"
dialect "java"
activation-group "group1"
when
$croNumberDetailsRequest : CRONumberDetailsRequest()
$resdirectPhoneNumber : ResdirectPhoneNumber()
eval($resdirectPhoneNumber.getType().getId() == 5 &&

$resdirectPhoneNumber.isValidForBrand($croNumberDetailsRequest.getBrand(
)) &&
$croNumberDetailsRequest.getRegion() != null &&

$resdirectPhoneNumber.isValidRegion($croNumberDetailsRequest.getRegion()
) &&
$croNumberDetailsRequest.getLocale() != null &&

$resdirectPhoneNumber.isValidForLocaleId($croNumberDetailsRequest.getLoc
ale()) &&

$resdirectPhoneNumber.isValidSlot($croNumberDetailsRequest.getSlot()));

then
ResultList.add($resdirectPhoneNumber);
end

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--
Edson Tirelli
JBoss Drools Core Development
JBoss, a division of Red Hat @ www.jboss.com

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From forum: drools - user

RE: Drools, Performance issues on 4.0.7 Vs 2.5

2008-09-05T11:54:27Z

RE: [rules-users] Drools, Performance issues on 4.0.7 Vs 2.5

I'll say it before someone else...

Evals are the devil, avoid them. From memory, the newer drools handles old rules poorly, using extensive use of evals. It's the reason we have not moved up to the newest version yet. It's probably not pretty but you may have to rewrite/reconfigure your rules to avoid the use of evals, if that 3x performance is a significant issue.

-Michael

-----Original Message-----
From: rules-users-bounces@... [rules-users-bounces@...] On Behalf Of Rout, Sushanta (ThoughtMill)
Sent: Friday, September 05, 2008 10:32 AM
To: Rules Users List
Subject: [rules-users] Drools, Performance issues on 4.0.7 Vs 2.5

We were using Drools 2.5 version earlier. Now we have switched to drools
4.0.7. But we see significant issues with performance like drools 4.0.7
is three times slower than 2.5 . Has anybody encountered the issue?

Here is a sample of the rule, we have some more similar to this.
rule "test"
        dialect "java"
        activation-group "group1"
        when
                $croNumberDetailsRequest : CRONumberDetailsRequest()
                $resdirectPhoneNumber : ResdirectPhoneNumber()
                eval($resdirectPhoneNumber.getType().getId() == 5 &&

$resdirectPhoneNumber.isValidForBrand($croNumberDetailsRequest.getBrand(
)) &&
                         $croNumberDetailsRequest.getRegion() != null &&

$resdirectPhoneNumber.isValidRegion($croNumberDetailsRequest.getRegion()
) &&
                         $croNumberDetailsRequest.getLocale() != null &&


$resdirectPhoneNumber.isValidForLocaleId($croNumberDetailsRequest.getLoc
ale()) &&

$resdirectPhoneNumber.isValidSlot($croNumberDetailsRequest.getSlot()));

        then
                ResultList.add($resdirectPhoneNumber);
end

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From forum: drools - user

Drools, Performance issues on 4.0.7 Vs 2.5

2008-09-05T08:31:43Z

From forum: drools - user

Re: Drools & "Query by Example"?

2008-09-05T08:21:04Z

Hi Mark, Greg

Mark Proctor wrote:
> Someone poppe onto irc a few months back, claiming they did this for
> their company and would provide the code as a patch - never heard
> anything after that though :( So if that person is read, please
> upload your patch to JIRA :)

>> Maybe if it's useful enough an operator could be added to Drools
>> that does the same thing. "~=" maybe?

Using the function to simulate the open world assumption is a neat idea!
The eval() requirements not so much....

Mark, as I am not afraid of digging into the code base... any pointers
where I should start looking to add this behaviour? Some class or
package name would help as drools is not so small :)

cu, Michael
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From forum: drools - user

Multiple conditions in 'when' statement in rule using dsl

2008-09-05T08:07:42Z

I'm sure I'm missing something stupid somewhere, but I'm new...

I'm trying to use multiple conditions inside a 'when' using a dsl. There was no explicit description of how to do this in the docs when using a dsl. I tried separating the conditions with ',', and, && but none didn't work. No matter what, it seems to treat this as an OR.

I have multiple conditions laid out in a mapping file such as:

[condition][]There is a cl with drt of "{drt}"=CLMessage(drt=="{drt}")
[condition][]There is a cl with a dT of "{dT}"=CLMessage(dT=="{dT}")
...

Here is the rule:
rule "rule4"
when
There is a cl with drt of "12345"
There is a cl with a dT of "G"
then
Log "Rule 4"
end

For this example. there are 2 items, one that matches only one condition, and another that matches both conditions. However, the text "Rule 4" is printed twice.

Thanks

From forum: drools - user

Re: logging with WorkingMemoryEventListener

2008-09-05T08:07:20Z

You can override the toString method of InputObject to return the type information.

From: rules-users-bounces@...

To: Rules Users List
Sent: Fri Sep 05 22:31:04 2008
Subject: [rules-users] logging with WorkingMemoryEventListener

Hello,

I want to use WorkingMemoryEventListener and AgendaEventListener for logging.
But I have a generic InputObject as fact which has a parameter "type" to disitnguish between different fact types, but all facts are instances of the class InputObject, only the type Paramater has different values.
Therefore in the log using DefaultWorkingMemoryEventListener I see only that an Object of class InputObject is inserted but not which type teh Object has. Is it possible to configure the WorkingMemoryEventListener that also the type is logged?

Regards
Thomas

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From forum: drools - user

Re: Drools & "Query by Example"?

2008-09-05T08:02:30Z

Someone poppe onto irc a few months back, claiming they did this for their company and would provide the code as a patch - never heard anything after that though :(
So if that person is read, please upload your patch to JIRA :)

Mark
Greg Barton wrote:

--- On Fri, 9/5/08, Michael Zimmermann list@... wrote:

rule "MyRule"
when
  book(year==myYear, author==myAuthor ...)
then
  ....

This works only if all properties myYear, myAuthor ... are
present. If one is undefined, the rule does not match.


You could have a function that returns true if the properties match or the property is null:

boolean matchesOrNull(Object o, Object p) {
  return p == null ? true : ( o == null ? true : o.equals(p) );
}

Call it using eval in the conditions.

Maybe if it's useful enough an operator could be added to Drools that does the same thing.  "~=" maybe?

GreG




      
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From forum: drools - user

logging with WorkingMemoryEventListener

2008-09-05T07:31:04Z

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From forum: drools - user

Re: Drools & "Query by Example"?

2008-09-05T07:25:33Z

--- On Fri, 9/5/08, Michael Zimmermann <list@...> wrote:

> rule "MyRule"
> when
> book(year==myYear, author==myAuthor ...)
> then
> ....
>
> This works only if all properties myYear, myAuthor ... are
> present. If one is undefined, the rule does not match.

You could have a function that returns true if the properties match or the property is null:

boolean matchesOrNull(Object o, Object p) {
return p == null ? true : ( o == null ? true : o.equals(p) );
}

Call it using eval in the conditions.

Maybe if it's useful enough an operator could be added to Drools that does the same thing. "~=" maybe?

GreG

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From forum: drools - user

Drools & "Query by Example"?

2008-09-05T06:38:20Z

Hi there,

I am not really sure what is the best approach to model this the drools
way... So, what is the best approach using drools to find all objects of
a known type that fulfil certain criterias? Caveat: The number of
criterias is flexible and not known?

I know, that such a selection process can be defined as simple case of
constraint programming. Afaik this could be a problem for any rulebased
system. Yet we do not want to introduce another compontent as this leads
to dependency and communication issues.

Example:
Assume a class book with properties "author", "year", "id" and
"publisher". As our problem is more complex I want to test book
instances for the properties "author", "year" etc. in individual rules.
Now, given a list of books in the working memory I want to get answer to
the following questions:

- List all books with author="myName", id="123"
- List all book with publisher="Frank"

Due to the closed world assumption in Java and hence Drools, what is not
possible is:

rule "MyRule"
when
book(year==myYear, author==myAuthor ...)
then
....

This works only if all properties myYear, myAuthor ... are present. If
one is undefined, the rule does not match.

The System:
The system uses drools quite successfully for many tasks. All data
objects are persisted using db4o.

Currently, I can think of two different approaches:
1)
- Start with all objects in the working memory
- For each condition, if present, flag all objects, that do not
fulfil this condition, as invalid
- Afterwards, list / process all objects that are not marked as invalid

2)
- Start with no object in the working memory
- Construct a blank object of the type analyzed
- If a certain condition is present, add this conidtion to
the object
- Query the object database in db4o and add all valid matching
object to the working memory. (db4o supports QueryByExample)

The double negotiation in the first approach is hard to understand and
difficult to maintain. The second approach works reasonably well yet
moves some of the main application logic to another component.

So, any clues, pointers or ideas how to solve this problem in a better way?

cu, Michael
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From forum: drools - user

typed dsl variables

2008-09-04T09:41:09Z

Hi Pallav,
I just started a new gig, so I don't have my drools env all set up, but here are my suggestions to help you to really understand dsl's and build some powerful rules using them.

Quick, dirty, but you won't become a guru:
1. Download Drools 5.
2. Use the syntax for typed variables, and use regular expressions in your mapping file. For example,
[condition][]{varname:[a-zA-z0-9]+}\s+is\sa\s+Volume\s+where\s+....
3. Keep in mind that dsl entries are expanded in a rule in the order they are declared in the DSL mapping file.

How to really learn it...
1. D/L the source and build.
2. Run your app, but run it through a debugger with breakpoint in the DefaultExpander class, so you can see exactly how pattern matching is going on, and step by step how your mappings transform your rule. The rule below should have 3 mappings, the third one matching in two locations.

v1 is a Volume where status is "NV" and sourceId is 2 and volume is
1000

Also, check the blog at http://blog.athico.com/2008/06/allowing-variable-masks-in-dsl-grammar.html, and on the mailing list. I've posted several times in the last couple months on how to solve this very problem using typed DSL variables.

--Matt

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From forum: drools - user