It sounds like a bug. Can you get Drools source code and look at the unit test for this to make sure your scenario works there? The file is: drools-core/src/test/java/org/drools/base/EvaluatorFactoryTest.java Method is: testBigDecimal() Very easy to add your use case in there. Let us know what you find. Edson 2008/11/6 Marina <ppine7(a)yahoo.com&gt; > Hi, > > I'm getting unexpected results when when using BigDecimal objects for > matching in rules. > I'm generating DRL in my code, using freemaker. > > I have a RuleEngineNumericFact object which has two attributes: > String propertyName > BigDecimal propertyValue > > Below is an example of a rule where I try to match a RuleEngineNumericFact > object based on the two attributes: > > rule "aaa" > agenda-group "r1" > dialect "java" > when > (RuleEngineNumericFact( propertyName == "somename" , propertyValue > == 10.8 )) > then > String ruleId = drools.getRule().getName(); > firedRuleIDs.add(ruleId); > end > > > Then I create a new RuleEngineNumericFact object and set its propertyValue > as following: > > String stringValue = "10.8"; > BigDecimal propertyValue = new BigDecimal(stringValue, new > MathContext(10)); > > (I also tried to use default precision settings by creating the BigDecimal > value as: > BigDecimal propertyValue = new BigDecimal(stringValue); > ) > > When I insert this fact into the rule engine - the rule does not get > fired, so the fact does not match. > > One note: if the values are integeres (like, propertyValue == 100) - the > rule gets fired. So, it is only the floating point numbers that do not > match. > > I generate the DRL in my Java code, using freemaker, and I specify the > value that will be used in the rule for matching by calling toString() > method on a BigDecimal object that I get from my business code. The > toString() representation ends up to be the "10.8" value (for example). > According to the BigDecimal documentation, marshalling from/to the same > string representation shoudl still produce BigDecimal objects that will > return TRUE from the equals() method when compared. > > > any ideas why this is not working here? > How does Drools compare values of objects like BigDecimal? > > thanks, > Marina > > > > > > > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > -- Edson Tirelli JBoss Drools Core Development JBoss, a division of Red Hat @ www.jboss.com _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

Thanks, Edson. I do have the source code for Drools4.0.7. How do I build and run the unit tests? Marina ------------------------------ *From:* Edson Tirelli <tirelli(a)post.com&gt; *To:* Rules Users List <rules-users(a)lists.jboss.org&gt; *Sent:* Thursday, November 6, 2008 10:46:46 AM *Subject:* Re: [rules-users] using BigDecimal in rules It sounds like a bug. Can you get Drools source code and look at the unit test for this to make sure your scenario works there? The file is: drools-core/src/test/java/org/drools/base/EvaluatorFactoryTest.java Method is: testBigDecimal() Very easy to add your use case in there. Let us know what you find. Edson 2008/11/6 Marina <ppine7(a)yahoo.com&gt; > Hi, > > I'm getting unexpected results when when using BigDecimal objects for > matching in rules. > I'm generating DRL in my code, using freemaker. > > I have a RuleEngineNumericFact object which has two attributes: > String propertyName > BigDecimal propertyValue > > Below is an example of a rule where I try to match a RuleEngineNumericFact > object based on the two attributes: > > rule "aaa" > agenda-group "r1" > dialect "java" > when > (RuleEngineNumericFact( propertyName == "somename" , propertyValue > == 10.8 )) > then > String ruleId = drools.getRule().getName(); > firedRuleIDs.add(ruleId); > end > > > Then I create a new RuleEngineNumericFact object and set its propertyValue > as following: > > String stringValue = "10.8"; > BigDecimal propertyValue = new BigDecimal(stringValue, new > MathContext(10)); > > (I also tried to use default precision settings by creating the BigDecimal > value as: > BigDecimal propertyValue = new BigDecimal(stringValue); > ) > > When I insert this fact into the rule engine - the rule does not get > fired, so the fact does not match. > > One note: if the values are integeres (like, propertyValue == 100) - the > rule gets fired. So, it is only the floating point numbers that do not > match. > > I generate the DRL in my Java code, using freemaker, and I specify the > value that will be used in the rule for matching by calling toString() > method on a BigDecimal object that I get from my business code. The > toString() representation ends up to be the "10.8" value (for example). > According to the BigDecimal documentation, marshalling from/to the same > string representation shoudl still produce BigDecimal objects that will > return TRUE from the equals() method when compared. > > > any ideas why this is not working here? > How does Drools compare values of objects like BigDecimal? > > thanks, > Marina > > > > > > > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > -- Edson Tirelli JBoss Drools Core Development JBoss, a division of Red Hat @ www.jboss.com _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

The problem with BigDecimal is this: (new BigDecimal("43.0")).equals(new BigDecimal("43")) is evaluated to false but (new BigDecimal("43.0")).compareTo(new BigDecimal("43")) is evaluated to 0 => they are equal Note that you should use String in constructor instead of double otherwise you get something unpredictable - see http://java.sun.com/j2se/1.4.2/docs/api/java/math/BigDecimal.html#BigDeci... And because your evaluator uses equals, it is quite unusable. Is it possible to do some special wrapper for this type? Just for equality, other operations would be nice to look like "x * y" but with division you need to specify scale and therefore I think it is not possible to wrap it to some nice look. :-( Regards, Libor Edson Tirelli-3 wrote: > > It sounds like a bug. Can you get Drools source code and look at the > unit > test for this to make sure your scenario works there? The file is: > > drools-core/src/test/java/org/drools/base/EvaluatorFactoryTest.java > > Method is: > > testBigDecimal() > > Very easy to add your use case in there. > > Let us know what you find. > > Edson > > -- View this message in context: http://www.nabble.com/using-BigDecimal-in-rules-tp20362868p22539892.html Sent from the drools - user mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users