data manipulation
by Betto Bardi
Hi all,
We recently implemented Drools in a mortgage application process. The primary task of the business rule engine was to determine the fraud risk of an application. The application is delivered in XML format. We noticed that we were implementing a lot of data manipulation actions in the drl file itself. For example, the calculation of total income by calculating the sum of a number of elements or calculating the distance between two geo-locations based on zip codes. The actual evaluation rules acted on this 'derived' information.
When looking back the drl file contained a lot of code and looked pretty complicated compared to the actual evaluation rules. My question is, what is your opinion on data manipulation or transformation within the drl file? If the drl file is not the best place for this, what would you suggest for data manipulation?
Thanks,
Betto
16 years, 2 months
error getting values from working memory
by Fnu Mahalakshmi
Hi,
I am facing problem in getting modified data from my working memory to my output file.
I have added all my data to an ArrayList. Sent it to my Rules - modified the input.
Now I want it to display the data contained in the objects of my list.
Unable to do that as I can only map it to ArrayList<Object>
So I am not able to call the particular functions for displaying particular data.
I tried adding my data to a HashMap<Object,String> but then data does not get loaded in the working memory.
Please help!!!
Thank you
M
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16 years, 2 months
Multiple Files Problem
by Fnu Mahalakshmi
Hi,
I need to load data contained in many Lists as my input.
In what way is it possible for me to load multiple lists in drools?
I am doing this currently:
public void runStatelessRules(String[] rulesFiles,String dslFileName,Collection<Object>al,
String ruleFlowFileName) throws Exception {
RuleBase ruleBase = loadRules(rulesFiles);
StatelessSession workingMemory = ruleBase.newStatelessSession();
workingMemory.execute(al);
}
Collection<Object>al is my input. In this I have dumped data from multiple arrayLists.
All rules get processed accurately.
But creates a mess when I need to write to my output file.
Is it in some way possible for me to give separate lists to load to my working memory???
Please help. Thanks in advance.
-M
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16 years, 2 months
Re: [rules-users] Multiple Object Referencing error
by Fnu Mahalakshmi
Hi guys,
Thanks a lot for looking into it. I just solved it. There were multiple objects getting created of the same type due to which rules was not getting fired. The error shown was very misleading :(
Thanks again
M
-----Original Message-----
From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of rules-users-request(a)lists.jboss.org
Sent: Tuesday, June 08, 2010 11:37 AM
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Today's Topics:
1. Re: Multiple Object referencing error (Fnu Mahalakshmi)
2. Re: Multiple Object referencing error (Swindells, Thomas)
3. smooks query (Fnu Mahalakshmi)
4. Re: Drools 5.1.0.M2 - BPMN2 process issue - Eclipse plugin.
-- The method getTextContent() is undefined for the type Node
(Vijay K Pandey)
----------------------------------------------------------------------
Message: 1
Date: Tue, 8 Jun 2010 10:13:15 -0400
From: Fnu Mahalakshmi <FMahalakshmi(a)nyx.com>
Subject: Re: [rules-users] Multiple Object referencing error
To: "'rules-users(a)lists.jboss.org'" <rules-users(a)lists.jboss.org>
Message-ID:
<994758E35590274E955FA75763C5AA5002D01087(a)MTEXMBXP01.ad.NYX.com>
Content-Type: text/plain; charset="us-ascii"
Hi,
Sorry about not posting the code. My mistake.
Classes :
public class Room {
private String name
private int number;
// getter and setter methods here
}
public classs Sprinkler {
private Room room;
private boolean on;
// getter and setter methods here
}
public class Fire {
private Room room;
// getter and setter methods here
}
I load 2 input files: 1. with data of fire and Room { f1, r1;f2, r2}
2. with data of sprinkler and Room {"n/a",r1,"n/a",r3}
I am writing rule " if fire exists in room start sprinkler" { so if f1 and r1 in this case: I should get s1, r1 } But since no sprinkler in r2 , That data should not get outputted.
I want my ouput file to look like:
Name Number
Xyz 1
# xyz is my room name and 1 is the room number : r1(xyz,1) . But I am unable to delete entries.Is there anyway I can do it?
#only this should appears as the other room does not have a sprinkler.
when
Fire($room : room)
$sprinkler : Sprinkler( room == $room, modified == false )
Then
$sprinkler.setmodified(true);
modify( $sprinkler ) { setSprinkle( "s1" ) };
end
Error:
I am getting the error at a place where I am trying to write back from my working memory to my output file.
It is happening because the second rule to turn on the sprinkler does not work and as a result a null value is getting stored.
Is it possible that there can exists 2 different Room() objects with the same room.name ??
Because the room objects are getting stored from different files to the working memory ??
Do you think it better to store room objects in a separate list??
I store all information into a list and load that into the memory.
Am I going wrong here?
Please help.
Thank you.
-M
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------------------------------
Message: 2
Date: Tue, 8 Jun 2010 15:20:54 +0100
From: "Swindells, Thomas" <TSwindells(a)nds.com>
Subject: Re: [rules-users] Multiple Object referencing error
To: Rules Users List <rules-users(a)lists.jboss.org>
Message-ID:
<DAC86F5F3B84F14088F0DB16092558CA07E8F9EC5D(a)UKMA1.UK.NDS.COM>
Content-Type: text/plain; charset="us-ascii"
You've still missed out the file which actually contains the main method which is where the exception is being thrown from...
> -----Original Message-----
> From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-
> bounces(a)lists.jboss.org] On Behalf Of Fnu Mahalakshmi
> Sent: 08 June 2010 15:13
> To: 'rules-users(a)lists.jboss.org'
> Subject: Re: [rules-users] Multiple Object referencing error
>
> Hi,
> Sorry about not posting the code. My mistake.
>
> Classes :
>
> public class Room {
> private String name
> private int number;
> // getter and setter methods here
> }
> public classs Sprinkler {
> private Room room;
> private boolean on;
> // getter and setter methods here
> }
> public class Fire {
> private Room room;
> // getter and setter methods here
> }
>
>
> I load 2 input files: 1. with data of fire and Room { f1, r1;f2, r2}
>
> 2. with data of sprinkler and Room {"n/a",r1,"n/a",r3}
>
>
>
> I am writing rule " if fire exists in room start sprinkler" { so if f1 and r1
> in this case: I should get s1, r1 } But since no sprinkler in r2 , That data
> should not get outputted.
> I want my ouput file to look like:
> Name Number
> Xyz 1
>
> # xyz is my room name and 1 is the room number : r1(xyz,1) . But I am unable
> to delete entries.Is there anyway I can do it?
>
> #only this should appears as the other room does not have a sprinkler.
>
> when
>
> Fire($room : room)
>
> $sprinkler : Sprinkler( room == $room, modified == false )
>
> Then
>
> $sprinkler.setmodified(true);
>
> modify( $sprinkler ) { setSprinkle( "s1" ) };
>
> end
>
>
> Error:
> I am getting the error at a place where I am trying to write back from my
> working memory to my output file.
> It is happening because the second rule to turn on the sprinkler does not work
> and as a result a null value is getting stored.
> Is it possible that there can exists 2 different Room() objects with the same
> room.name ??
> Because the room objects are getting stored from different files to the
> working memory ??
> Do you think it better to store room objects in a separate list??
> I store all information into a list and load that into the memory.
> Am I going wrong here?
>
> Please help.
>
> Thank you.
> -M
> Please consider the environment before printing this email.
>
> Visit our website at http://www.nyse.com
>
> ****************************************************
>
> Note: The information contained in this message and any attachment to it is
> privileged, confidential and protected from disclosure. If the reader of this
> message is not the intended recipient, or an employee or agent responsible for
> delivering this message to the intended recipient, you are hereby notified
> that any dissemination, distribution or copying of this communication is
> strictly prohibited. If you have received this communication in error, please
> notify the sender immediately by replying to the message, and please delete it
> from your system. Thank you. NYSE Euronext.
>
>
> _______________________________________________
> rules-users mailing list
> rules-users(a)lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
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Message: 3
Date: Tue, 8 Jun 2010 11:30:17 -0400
From: Fnu Mahalakshmi <FMahalakshmi(a)nyx.com>
Subject: [rules-users] smooks query
To: "'rules-users(a)lists.jboss.org'" <rules-users(a)lists.jboss.org>
Message-ID:
<994758E35590274E955FA75763C5AA5002D01088(a)MTEXMBXP01.ad.NYX.com>
Content-Type: text/plain; charset="us-ascii"
Hi,
Can anyone point me towards a good documentation as to how smooks works with drools?
How does smooks transform non-XML(java) data?? I could not understand this part???
Thank you in advance,
M
</pre>
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16 years, 2 months
Flow exception handling
by Swindells, Thomas
Hi Everyone,
I'm trying to get my head round how to use Drools Flow in a reliable manner.
In particular I'm trying to understand how to defensively program against exceptions thrown within Action Nodes (eg NullPointerException).
In 5.0.1 it is absolutely horrendous as if the action throws an exception while being called from fireUntilHalt then the exception just gets swallowed up with no way for the application to detect it at all.
In 5.1.0-M1 it is marginally better in that the exception is thrown through fireUntilHalt (or whatever other location it is called from).
However there seems to be absolutely no way to determine which process is at fault - the process isn't even marked as Aborted and still exists in the session, also if you call fireUntilHalt again it just seems to sit there and not run any more processes. It doesn't even throw an IllegalState type exception to tell you it isn't valid to call it after an exception has occurred.
What I was expecting was that processes work in a similar way to java threads. If a particular process encounters an exception I would expect that:
1. The process is marked as aborted.
2. An appropriate method on a process event listener is called.
3. Any other processes in the session will attempt to continue to run.
Clearly depending on your session configuration the working memory may be in an invalid state and other processes may be stuck waiting for an event to occur which never will, but this is a design decision for the application developer, in many other cases processes will be stand alone keeping all their data internal to themselves.
Is there some other functionality of Drools that I am missing or should I raise a JIRA for this (if one doesn't already exist).
Thomas
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16 years, 2 months
Re: [rules-users] Drools 5.1.0.M2 - BPMN2 process issue - Eclipse plugin. -- The method getTextContent() is undefined for the type Node
by Vijay K Pandey
Update::: Issues related to Plugin. When I recompiled the bpmn2 src and put that jar in the plugin lib, it simply didn't took the recompiled version. Then I removed the jar from the plugin lib and simply copied the - bpmn2 classes directly in the org/drools package of the plugin and voila - plugin started working fine.
Thanks
Vijay
From: Vijay K Pandey
Sent: Tuesday, June 08, 2010 8:48 AM
To: 'Rules Users List'
Subject: RE: Drools 5.1.0.M2 - BPMN2 process issue - Eclipse plugin. -- The method getTextContent() is undefined for the type Node
Update::: On the exception(mentioned below) related to jar "drools-bpmn2-5.1.0.M2.jar", I recreated this jar file from the Drools source (5.1.0.M2) against JDK6 and the exception went away. :) So far so good.
Plugin related exception is still there. I replaced the jar "drools-bpmn2.jar" which is present in the lib of plugin jar "org.drools.eclipse_5.1.0.M2.jar" with the recompiled jar, but not much luck - plugin is still not able to open the "*.bpmn" process. The error I get is "The method getTextContent() is undefined for the type Node" .
Right now I am at a dead end. Thanks in advance for help.
Thanks
Vijay
From: Vijay K Pandey
Sent: Monday, June 07, 2010 5:45 PM
To: 'Rules Users List'
Subject: RE: Drools 5.1.0.M2 - BPMN2 process issue - Eclipse plugin. -- The method getTextContent() is undefined for the type Node
I created a sample project to run a very simple rule flow (BPMN process), I got the similar error which the plugin is reporting. My env is SUN JDK 6. Here is the exception I get? Any clue guys.
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
The method getTextContent() is undefined for the type Node
The method getTextContent() is undefined for the type Node
at org.drools.bpmn2.xml.StartEventHandler.handleNode(StartEventHandler.java:46)
at org.drools.bpmn2.xml.AbstractNodeHandler.end(AbstractNodeHandler.java:77)
at org.drools.xml.ExtensibleXmlParser.endElement(ExtensibleXmlParser.java:420)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(AbstractSAXParser.java:601)
at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:180)
at com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.emptyElement(XMLSchemaValidator.java:739)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:377)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2755)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:140)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:511)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:808)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:119)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
at javax.xml.parsers.SAXParser.parse(SAXParser.java:395)
at org.drools.xml.ExtensibleXmlParser.read(ExtensibleXmlParser.java:295)
at org.drools.xml.ExtensibleXmlParser.read(ExtensibleXmlParser.java:174)
at org.drools.compiler.xml.XmlProcessReader.read(XmlProcessReader.java:44)
at org.drools.compiler.ProcessBuilder.addProcessFromFile(ProcessBuilder.java:222)
at org.drools.compiler.PackageBuilder.addProcessFromXml(PackageBuilder.java:415)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:475)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:517)
at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
Thanks
Vijay
From: Vijay K Pandey
Sent: Sunday, June 06, 2010 11:43 PM
To: Rules Users List
Subject: Drools 5.1.0.M2 - BPMN2 process issue - Eclipse plugin. -- The method getTextContent() is undefined for the type Node
Hi,
I just downloaded the Drools 5.1.0.M2 (have been using the snapshot version of around 16th April 2010) - created a sample "rule flow file(start-->user task-->end) - bpmn2 version". But when I clicked the file to open it gave the following error (image attached)
"The method getTextContent() is undefined for the type Node" .
I understand this error is related to org.w3c.dom.Node where this method was added as part of DOM Level 3 and available in JDK 5+ . My project and eclipse is configured against JDK 6+ . Not sure why this error with M2.
May be it is because of the drools-bpmn2.jar included in the drools eclipse plugin? Can someone shed some light that where it might be going wrong.
[cid:image001.png@01CB06F6.8568A3E0]
Thanks
Vijay
16 years, 2 months
smooks query
by Fnu Mahalakshmi
Hi,
Can anyone point me towards a good documentation as to how smooks works with drools?
How does smooks transform non-XML(java) data?? I could not understand this part???
Thank you in advance,
M
</pre>
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16 years, 2 months
Re: [rules-users] Multiple Object referencing error
by Fnu Mahalakshmi
Hi,
Sorry about not posting the code. My mistake.
Classes :
public class Room {
private String name
private int number;
// getter and setter methods here
}
public classs Sprinkler {
private Room room;
private boolean on;
// getter and setter methods here
}
public class Fire {
private Room room;
// getter and setter methods here
}
I load 2 input files: 1. with data of fire and Room { f1, r1;f2, r2}
2. with data of sprinkler and Room {"n/a",r1,"n/a",r3}
I am writing rule " if fire exists in room start sprinkler" { so if f1 and r1 in this case: I should get s1, r1 } But since no sprinkler in r2 , That data should not get outputted.
I want my ouput file to look like:
Name Number
Xyz 1
# xyz is my room name and 1 is the room number : r1(xyz,1) . But I am unable to delete entries.Is there anyway I can do it?
#only this should appears as the other room does not have a sprinkler.
when
Fire($room : room)
$sprinkler : Sprinkler( room == $room, modified == false )
Then
$sprinkler.setmodified(true);
modify( $sprinkler ) { setSprinkle( "s1" ) };
end
Error:
I am getting the error at a place where I am trying to write back from my working memory to my output file.
It is happening because the second rule to turn on the sprinkler does not work and as a result a null value is getting stored.
Is it possible that there can exists 2 different Room() objects with the same room.name ??
Because the room objects are getting stored from different files to the working memory ??
Do you think it better to store room objects in a separate list??
I store all information into a list and load that into the memory.
Am I going wrong here?
Please help.
Thank you.
-M
Please consider the environment before printing this email.
Visit our website at http://www.nyse.com
****************************************************
Note: The information contained in this message and any attachment to it is privileged, confidential and protected from disclosure. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify the sender immediately by replying to the message, and please delete it from your system. Thank you. NYSE Euronext.
16 years, 2 months
Exception using persistence
by Robert
Hi, I followed the instructions on setting up the persistence in the
drools flow doc, but I get the following exception:
Exception in thread "main" java.lang.RuntimeException: Could not commit
session
at
org.drools.persistence.session.SingleSessionCommandService.<init>(SingleSessionCommandService.java:133)
at
org.drools.persistence.jpa.impl.JPAKnowledgeServiceProviderImpl.newStatefulKnowledgeSession(JPAKnowledgeServiceProviderImpl.java:44)
at
org.drools.persistence.jpa.JPAKnowledgeService.newStatefulKnowledgeSession(JPAKnowledgeService.java:93)
at
com.rob.server.core.process.drools.tasks.DroolsProcessHandler.<init>(DroolsProcessHandler.scala:130)
at
com.rob.server.core.process.drools.tasks.StartDroolsProcessHandler$.main(DroolsProcessHandler.scala:33)
at
com.rob.server.core.process.drools.tasks.StartDroolsProcessHandler.main(DroolsProcessHandler.scala)
Caused by: javax.naming.NameNotFoundException; remaining name
'UserTransaction'
at org.eclipse.jetty.jndi.NamingContext.lookup(NamingContext.java:576)
at org.eclipse.jetty.jndi.NamingContext.lookup(NamingContext.java:663)
at org.eclipse.jetty.jndi.NamingContext.lookup(NamingContext.java:678)
at
org.eclipse.jetty.jndi.java.javaRootURLContext.lookup(javaRootURLContext.java:110)
at javax.naming.InitialContext.lookup(InitialContext.java:392)
at
org.drools.persistence.session.SingleSessionCommandService.<init>(SingleSessionCommandService.java:109)
... 5 more
I have no idea what this means. I guess SingleSessionCommandService is
looking up for "UserTransaction", but whats the "UserTransaction" ?
Cheers, Rob.
--
Erstellt mit Operas revolutionärem E-Mail-Modul: http://www.opera.com/mail/
16 years, 2 months
Re: [rules-users] Multiple Object Referencing problem
by Fnu Mahalakshmi
Hi Esteban,
I am getting the error at a place where I am trying to write back from my working memory to my output file.
It is happening because the second rule to turn on the sprinkler does not work and as a result a null value is getting stored.
Is it possible that there can exists 2 different Room() objects with the same room.name ??
Because the room objects are getting stored from different files to the working memory ??
Do you think it better to store room objects in a separate list??
I store all information into a list and load that into the memory.
Am I going wrong here?
Please help.
Thank you.
-M
-----Original Message-----
From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of rules-users-request(a)lists.jboss.org
Sent: Tuesday, June 08, 2010 8:40 AM
To: rules-users(a)lists.jboss.org
Subject: rules-users Digest, Vol 43, Issue 36
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Today's Topics:
1. Re: Multiple Object Referencing problem (Esteban Aliverti)
2. Re: Exception using persistence (Alan.Gairey(a)tessella.com)
----------------------------------------------------------------------
Message: 1
Date: Tue, 8 Jun 2010 09:25:47 -0300
From: Esteban Aliverti <esteban.aliverti(a)gmail.com>
Subject: Re: [rules-users] Multiple Object Referencing problem
To: Rules Users List <rules-users(a)lists.jboss.org>
Message-ID:
<AANLkTilCFcZwhX6uthWz3tIvkJXdtqVKXcb0uG-rqm91(a)mail.gmail.com>
Content-Type: text/plain; charset="windows-1252"
Look at the line 58 of RulesTest class and you will find the problem. Try to
always analyse the stacktrace if there are no drools classes involved, then
it is not a Drools error. And remember, the debugger is your friend ;)
Best,
2010/6/7 David Sinclair <dsinclair(a)chariotsolutions.com>
> This has nothing to do with Drools. It looks like you are giving Writer bad
> input perhaps??
>
> Exception in thread "main" *java.lang.NullPointerException*
>
> at java.io.Writer.write(Unknown Source)
>
> at com.org.RulesTest.main(*RulesTest.java:58*)
>
>
>
>
> 2010/6/7 Fnu Mahalakshmi <FMahalakshmi(a)nyx.com>
>
>> Hi,
>>
>>
>>
>> I am trying out this example from the book :
>>
>> public class Room {
>>
>> private String name
>>
>> // getter and setter methods here
>>
>> }
>>
>> public classs Sprinkler {
>>
>> private Room room;
>>
>> private boolean on;
>>
>> // getter and setter methods here
>>
>> }
>>
>> public class Fire {
>>
>> private Room room;
>>
>> // getter and setter methods here
>>
>> }
>>
>>
>>
>> I load 2 input files: 1. with data of fire and Room { f1, r1;f2, r2}
>>
>> 2. with data of sprinkler and Room { ? ?, r1; ?
>> ? , r2}
>>
>>
>>
>> I am writing rule ? if fire exists in room start sprinkler? { so if f1 and
>> r1 in this case: I should get s1, r1 }
>>
>> when
>>
>> Fire($room : room)
>>
>> $sprinkler : Sprinkler( room == $room, modified == false )
>>
>> Then
>>
>> $sprinkler.setmodified(true);
>>
>> modify( $sprinkler ) { setSprinkle( ?s1? ) };
>>
>> end
>>
>>
>>
>> But this gives me error:
>>
>> Exception in thread "main" *java.lang.NullPointerException*
>>
>> at java.io.Writer.write(Unknown Source)
>>
>> at com.org.RulesTest.main(*RulesTest.java:58*)
>>
>>
>>
>> From what I observed this rule is not getting fired at all.
>>
>> I want this rule to be fired on the data in my second input file.
>>
>> The rules for my first input file get executed properly.
>>
>>
>>
>> Can any1 tell me where I am going wrong??
>>
>> Is there any way in which we can use the modified data { after rules are
>> fired on the first input data and it is modified}to fire another set of
>> rules on the same input depending on the next input file???
>>
>>
>>
>> Thank you.
>>
>>
>>
>> -M
>>
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Esteban Aliverti
16 years, 2 months
