NPE when retracting the objects in working memory...
by Reddy Ramesh-in2259c
Hi,
I am getting null pointer exception when i retract objects from working
memory. please help me in resolving this problem....
my rule goes like this...
package com.moto.nms
import com.moto.nms.Event;
import com.adventnet.nms.topodb.ManagedObject;
import com.motorola.nmatg.nms.topology.ManagedEntity;
global com.moto.nms.Consecutive con; // Consecutive is an simple
class file which has two simple methods, getValue() and setValue().
rule "duplicate"
salience 29
when
e1 : Event( firsttime1 : time , severity1 : severity == 1 )
e2 : Event( firsttime2 : time > firsttime1 , severity == severity1 )
not Event( severity == -1 , time > firsttime1 , time < firsttime2)
then
System.out.println("matched the fact");
e1.setCompressionStatus("compress_"+con.getValue());
e2.setCompressionStatus("compress_"+con.getValue());
end
rule "duplicate_x"
salience 29
when
e1 : Event(firsttime1 : time , severity == 1 )
e2 : Event(firsttime2 : time > firsttime1 , severity == 1)
exists Event( severity == -1, time > firsttime1 , time < firsttime2)
then
System.out.println("matched 2nd fact");
con.setValue(con.getValue() +1);
end
exception is like this...
Caught Exceptionjava.lang.NullPointerException
java.lang.NullPointerException
at org.drools.reteoo.beta.DefaultRightMemory.remove(Unknown Source)
at org.drools.reteoo.BetaMemory.remove(Unknown Source)
at org.drools.reteoo.NotNode.retractObject(Unknown Source)
at org.drools.reteoo.ObjectSource.propagateRetractObject(Unknown Source)
at org.drools.reteoo.RightInputAdapterNode.retractTuple(Unknown Source)
at org.drools.reteoo.TupleSource.propagateRetractTuple(Unknown Source)
at org.drools.reteoo.NotNode.retractTuple(Unknown Source)
at org.drools.reteoo.TupleSource.propagateRetractTuple(Unknown Source)
at org.drools.reteoo.JoinNode.retractTuple(Unknown Source)
at org.drools.reteoo.LeftInputAdapterNode.retractObject(Unknown Source)
at org.drools.reteoo.ObjectSource.propagateRetractObject(Unknown Source)
at org.drools.reteoo.AlphaNode.retractObject(Unknown Source)
at org.drools.reteoo.ObjectSource.propagateRetractObject(Unknown Source)
at org.drools.reteoo.ObjectTypeNode.retractObject(Unknown Source)
at org.drools.reteoo.Rete.retractObject(Unknown Source)
at org.drools.reteoo.ReteooRuleBase.retractObject(Unknown Source)
at org.drools.reteoo.ReteooWorkingMemory.doRetract(Unknown Source)
at org.drools.common.AbstractWorkingMemory.retractObject(Unknown Source)
at org.drools.common.AbstractWorkingMemory.retractObject(Unknown Source)
at com.moto.nms.TestEvents3.retractAll(TestEvents3.java:219)
at com.moto.nms.TestEvents3.readRule(TestEvents3.java:158)
at com.moto.nms.TestEvents3.main(TestEvents3.java:242)
TestEvents3.java class is like this....
package com.moto.nms;
//related to IO..
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.InputStream;
import java.util.List;
import java.util.Iterator;
//related to Drools..
import org.drools.RuleBase;
import org.drools.RuleBaseFactory;
import org.drools.compiler.PackageBuilder;
import org.drools.rule.Package;
import org.drools.WorkingMemory;
import org.drools.FactHandle;
import org.drools.FactException;
import com.moto.nms.Event;
import com.moto.nms.NMSEvent;
import com.moto.nms.TopoInterface1;
import com.moto.nms.GenerateEvents;
import com.adventnet.nms.topodb.ManagedObject;
import com.moto.nms.Consecutive;
public class TestEvents3 {
private Reader reader;
private RuleBase rulebase;
private WorkingMemory wm;
private List factHandles;
public TestEvents3(){
}
public void readRule(String readername) throws Exception{
InputStream str = null;
str = TestEvents.class.getResourceAsStream(readername);
if(str == null)
{
System.out.println("unable to read rule file");
return;
}
reader = new InputStreamReader(str); //read in the source
PackageBuilder builder = new PackageBuilder(); //building up the rule
package
builder.addPackageFromDrl(reader);
Package pkg = builder.getPackage(); //get the compiled package
rulebase = RuleBaseFactory.newRuleBase();
rulebase.addPackage( pkg ); //adding the package to the rule base
Consecutive con = new Consecutive();
wm = rulebase.newWorkingMemory();
wm.setGlobal("con", con);
System.out.println("\n\n"+System.currentTimeMillis());
Event ev1 = new Event(183, 1, "port02", "LOS",
System.currentTimeMillis());
//Thread.sleep(450);
Event ev9 = new Event(192, 1, "port02", "LOS",
System.currentTimeMillis());
//Thread.sleep(400);
Event ev10 = new Event(307, 1, "port02", "LOS",
System.currentTimeMillis());
Thread.sleep(500);
Event ev11= new Event(306, 1, "port02", "LOS",
System.currentTimeMillis());
Thread.sleep(200);
Event ev12= new Event(305, 1, "port02", "LOS",
System.currentTimeMillis());
Thread.sleep(250);
Event ev13= new Event(304, -1, "port02", "LOS",
System.currentTimeMillis());
Thread.sleep(600);
Event ev14= new Event(302, 1, "port02", "LOS",
System.currentTimeMillis());
Thread.sleep(200);
Event ev15= new Event(301, 1, "port02", "LOS",
System.currentTimeMillis());
Thread.sleep(200);
Event ev16= new Event(308, 1, "port02", "LOS",
System.currentTimeMillis());
wm.assertObject(ev1);
wm.assertObject(ev9);
wm.assertObject(ev10);
wm.assertObject(ev11);
wm.assertObject(ev12);
wm.assertObject(ev13);
wm.assertObject(ev14);
wm.assertObject(ev15);
wm.assertObject(ev16);
System.out.println("\n\n"+System.currentTimeMillis());
System.out.println("\n\nFiring rules...\n");
wm.fireAllRules();
factHandles = wm.getObjects();
System.out.println("\n\nAll the Objects in WOrking Memory are as
Follows...\n");
for(int i=0; i<factHandles.size(); i++)
{
System.out.println(factHandles.get(i));
}
System.out.println("The CompressionStatus of the events are...");
System.out.println(ev1.getCompressionStatus());
System.out.println(ev9.getCompressionStatus());
System.out.println(ev10.getCompressionStatus());
System.out.println(ev11.getCompressionStatus());
System.out.println(ev12.getCompressionStatus());
System.out.println(ev13.getCompressionStatus());
System.out.println(ev14.getCompressionStatus());
System.out.println(ev15.getCompressionStatus());
System.out.println(ev16.getCompressionStatus());
System.out.println("The DeletionStatus of the events are...");
System.out.println(ev1.getDeletionStatus());
System.out.println(ev9.getDeletionStatus());
System.out.println(ev10.getDeletionStatus());
System.out.println(ev11.getDeletionStatus());
System.out.println(ev12.getDeletionStatus());
System.out.println(ev13.getDeletionStatus());
System.out.println(ev14.getDeletionStatus());
System.out.println(ev15.getDeletionStatus());
System.out.println(ev16.getDeletionStatus());
Thread.sleep(1000);
System.out.println("Starting retracting....");
Thread.sleep(1000);
retractAll();
System.out.println(System.currentTimeMillis());
}
public void retractAll()
{
factHandles = wm.getFactHandles();
Iterator itr = factHandles.iterator();
if(factHandles == null)
{
System.out.println("invalid FactHandler List");
return;
}
System.out.println("size of fact handles..:"+factHandles.size());
while(itr.hasNext())
{
try{
FactHandle fh = (FactHandle)itr.next();
if(fh == null)
System.out.println("Here object is null, Cannot be retracted");
else
{
wm.retractObject(fh);
System.out.println("Retracted object : "+ fh);
}
}catch (FactException e){
e.printStackTrace();
}
}
return;
}
public static void main(String[] args){
TestEvents3 te = new TestEvents3();
try{
te.readRule("/AlarmSuppression.drl");
}catch(Exception ex){
System.out.println("Caught Exception" +ex);
ex.printStackTrace();}
}
}
Thanks,
RameshReddy,
Trainee,
Motorola India.
19 years
Correlation of events
by Framewala, Ashfaq Y
Hi,
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following
rule "new error"
when
$error : Error (state == NEW_ERROR)
then
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registered)
if (found)
{
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I've just started working on a project that will make use of Decision Tables
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Any help would be much appreciated!!
--
View this message in context: http://www.nabble.com/Decision-Tables-and-Application-Deployment-tf327690...
Sent from the drools - user mailing list archive at Nabble.com.
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by Amarendra Mishra
Hi,
I am trying to write a protoype with JBoss Rules 3.0.5
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rule "CompDept Product Qualification Rule"
salience 7
no-loop true;
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$cust:( Customer( productIDs contains "Computer")
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# Customer(compDeptState == Customer.NOTRUN) <-------- Commented line
then
$cust.setCompDeptState (Customer.DONE);
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$cust.addQualifiedProduct("CompDeptProduct");
System.out.println("CompDeptProduct qualified...." );
modify($cust);
end
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If I run the above rule it goes in recursive mode (I have another rule in the drl that also acts on the same customer object and modifies it).
If I uncomment the commented line my LHS it's not evaluating to true and RHS is not running.
Any help would be appreciated.
Kind Regards,
Amarendra.
____________________________________________________________________________________
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Download and play hundreds of games for free on Yahoo! Games.
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by Francisco Brum
Hi everybody!
I would like to be able to access the data base during the execution of a rule.
The reason it's because instead of asserting in the working memory information as a global, it would be easy to make a SQL query using hibernate to consult the information.
Can I implement this in a function of my global fact or there is another way?
Thanks in advance for your attention!
__________________________________
Francisco Brum - francisco.brum(a)link.pt <mailto:rui.arrenega@link.pt>
Link Consulting - http://www.link.pt/ <http://www.link.pt/>
Tel.: 213 100 031
Av. Duque D'Ávila, 23 4º Esq.
1000-138 Lisboa
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When my rule fires I want to decrease the temperature level to simulate that
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This works ONE time when I set the new value on Thermometer and modify
Thermometer, not reaching A (the rule isnt fired again).
But works as expected when I modify Room instead of Thermometer (rules is
fired several times).
I'm new to drools and wonder if that is desired or if I do something wrong.
To make things more confusing: When several rules met the same conditions,
does only one rule gets fired or do all get fired (as I read it from Figure
1.19 of the documention).
If I modify Room my other rules _dont_ get fired. When I had modified
Thermometer my other rules _do_ get fired.
Is there anyone who can shed a little light on that for me?
--
View this message in context: http://www.nabble.com/modify-object-Tree--tf3268137.html#a9085281
Sent from the drools - user mailing list archive at Nabble.com.
19 years
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by Johnson, Brad
Hello
I am using the rules engine within a Jini service. It seems to work
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Rules log messages.
Is there some adaptor to connect up the way Rules does logging with
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Thanks
Brad
19 years
Autoboxing
by wernejen＠TU-Cottbus.De
Hi everbody,
I'm trying to translate an other rule-language in JBossRules (with
XSL(T)).
One of my major problems is the autoboxing- without unboxing-support in
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I think it is a general problem, because (1) everyone who is writing a
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to be used are. I think it is enough to know is it a digit, a boolean
or... The trouble begins in an evaluation:
when
Person ($age1 : age, name == 'Mike')
Person ($age2 : age, name == 'Peter')
eval ($age1 > $age2) // !!! it's wrong
eval ($age1.intValue() > $age2.intValue()) // it's ok if the Objects
// are Integer and not
// Double or ...
..
I think a rule-creator without java-knowlege has only little
understanding for this. (... and rules are for specialist from different
domains???)
(2) another conflict is in the different handling in fieldconstraints and
evaluations.
I can use all operators for simple types in field constraints but not in
evaluations:
when
Person (age > 20) // here I use the field as a primintiv type
Person (age < 30)
..
I know that all of them based on java and oop and I need this knowledge
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from other domains.
I don't know, what the reason for autoboxing (without unboxing
especially in java 5) is.
I'm confused by the documentation.
(Drools Documentation: "... If you use Java 5, then you get the best of
both worlds ..." (context autoboxing).
Another line in the drool documentation: "All bound primitive
declarations are boxed, there is currently no auto-unboxing (if you use
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Will the unboxing be supported in futur versions?
(... or afford a possibility for switch off the autoboxing?)
Thanks,
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19 years
RE: [rules-users] debugging with 3.1M1 IDE?
by Anstis, Michael (M.)
Barry, on reading your email I downloaded the current binaries and
followed the installation instructions for the Eclipse plugin. I simply
copied org.drools.ide_3.1.0.1.jar to
<eclipse-install>\sdk-3.2.1\eclipse\plugins and I could put breakpoints
in the RHS of my rules. I started a new debug configuration in Eclipse
by clicking on the "Debug..." on the dropdown list beside the "bug" icon
and choosing a new "Drools Application".
Sorry all appears OK to me :-(
Mike
-----Original Message-----
From: rules-users-bounces(a)lists.jboss.org
[mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Barry Kaplan
Sent: 22 February 2007 14:25
To: Rules Users List
Subject: Re: [rules-users] debugging with 3.1M1 IDE?
Well, I just checked out head and rebuilt the IDE with both the feature
and plugin. But I get no drools launch type....
(BTW, The ant/maven build seem to run clean. But importing the drools
projects into eclipse results in lots of projects with errors. Is this
expected for M1.)
-barry
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19 years
