This is precisely how I expect it to be expressed. When I express in this way I get this error message: BuildError: Unable to create Field Extractor for 'loanToValue' of '[ClassObjectType class=com.nathean.rules.IndividualDecision]' in rule 'G2 Equity in Asset' even though it is a variable in my IndividualDecision class. I have 3 other rule files that have expression in this simple manner and they produce no errors and are fine. But for this, It only lets me use eval or have something like this: *rule* "G2 Equity in Asset" *ruleflow-group* "goods" *when* $d : IndividualDecision() Individual($d.loanToValue < 85.0) *then* … //System.out.println((Double.valueOf("85")).doubleValue()); System.out.println("loanToValue: " + ($d.getLoanToValue())); *End* I understand that it is pointless having that 2nd line in the when section, but it’s the only way it picks up the variables in the IndividualDecision class with no errors. I don’t know why I can’t do this with this particular rules file. I am using Eclipse. Could there be some drools configuration issue with this file? -A ------------------------------ *From:* rules-users-bounces(a)lists.jboss.org [mailto: rules-users-bounces(a)lists.jboss.org] *On Behalf Of *Wolfgang Laun *Sent:* 12 April 2010 14:30 *To:* Rules Users List *Subject:* Re: [rules-users] Double Handling Well, then drop the dialect "mvel" and write the pattern as $d : IndividualDecision( loanToVal < 85.0 ) There's no visible need to use mvel. Or eval: the simplest form for constraints is always best. -W 2010/4/12 Ade Timi <adeyinka.timi(a)nathean.com&gt; Many thanks for the response! Yes it fires when I use 85.0 instead, but it obviously shouldn’t as the condition is false. My code now looks like this: *rule* "G2 Equity in Asset" *ruleflow-group* "goods" *dialect* "mvel" *when* $d : IndividualDecision(*eval*($d.getLoanToValue() < 85.0)) *then* $d.setGoodCount($d.incGoodCount()); $d.setMessage("0065: G2: Good: Good Equity in Deal"); //System.out.println((Double.valueOf("85")).doubleValue()); System.out.println("loanToValue: " + ($d.getLoanToValue())); *end* I still get the print output of 92000.0, which is as I expect but I don’t expect the rule to be fired at all. The weird thing is that when I change the condition to ‘>’ which is the true condition it never fires! I’m at a loss as to why this is happening. - Ade ------------------------------ *From:* rules-users-bounces(a)lists.jboss.org [mailto: rules-users-bounces(a)lists.jboss.org] *On Behalf Of *Wolfgang Laun *Sent:* 11 April 2010 09:11 *To:* Rules Users List *Subject:* Re: [rules-users] Double Handling You are comparing a double to a String ("85"). Although MVEL might convert strings to numbers, I wouldn't use this without some cogent reason. Do you have this unexpected firing also when you use a double literal, i.e., 85.0 ? -W 2010/4/9 Ade Timi <adeyinka.timi(a)nathean.com&gt; Hi, I am new to Drools. I am having a problem comparing 2 double values. I have a Java class with a double attribute called loanToValue. The loanToValue is been read from an XML file and the value is 92000.0. Based on this value I do not expect this rule to be fired, but for some reason it does. And the print statement returns 92000.0. Does anyone know what I’m doing wrong? My rule looks as follows: *rule* "G2 Equity in Asset" *ruleflow-group* "goods" *dialect* "mvel" *when* $d : IndividualDecision() Individual(*eval*($d.getLoanToValue() < "85")) *then* System.out.println("loanToValue: " + ($d.getLoanToValue())); *end* * * Thanks, Ade *Adeyinka Timi* | Technical Supprt | *Nathean Technologies Ltd* Registered Office 3 Lyncon Court, IDA Science & Technology Park, Snugborough Road, Blanchardstown, Dublin 15, Ireland *T +353 1 685 3001* | VOIP 076 615 1117 | *E adeyinka.timi(a)nathean.com* | <http://www.nathean.com/>www.nathean.com Incorporated in Ireland, No. 339972 The information appearing in this email and any files transmitted with it is confidential and may not be reproduced, modified, distributed, transmitted, displayed, published or broadcast without the prior written permission of Nathean Technologies Ltd. It is intended solely for the use of the addressee(s). Nathean Technologies Ltd, its directors, officers and employees do not accept liability for any loss or damage of any nature howsoever arising pertaining to the use of information appearing in this email and/or any files transmitted with it. Whilst this email has been checked for the presence of computer viruses, Nathean Technologies Ltd does not, except as required by law, represent, warrant and/or guarantee that the integrity of this communication has been maintained nor that the communication is free of errors, viruses, interception or interference. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

Thanks guys for your responses. This should be as simple as it gets, which adds to my frustration. See the following code below: *Java classes:* *Individual* – *public* *class* Individual { *private double assetCost;* * * *public* *void* setAssetCost(*double* assetCost) { *this*.assetCost = assetCost; } *public* *double* getAssetCost() { *return* assetCost; } } *IndividualDecision* – *public* *class* IndividualDecision { *private double loanToValue;* * * *public* *void* setLoanToValue(*double* LoanToValue) { *this*.loanToValue = LoanToValue; } *public* *double* getLoanToValue() { *return* loanToValue; } *public* *void* calcValues(Individual ind){ *this*.loanToValue = ind.getAssetCost(); } } *Rule Resourse – * * **import* com...Individual *import* com...IndividualDecision *rule* "G2 Equity in Asset" *when* $d : IndividualDecision(loanToValue() < 85.0) *then* System.out.println("loanToValue: " + ($d.getLoanToValue())); *End* * * Hope this helps! Many Thanks again ------------------------------ *From:* rules-users-bounces(a)lists.jboss.org [mailto: rules-users-bounces(a)lists.jboss.org] *On Behalf Of *Edson Tirelli *Sent:* 12 April 2010 15:46 *To:* Rules Users List *Subject:* Re: [rules-users] Double Handling Ade, All these errors you are seeing are totally strange, as this is one of the simplest things the rules engine does. Are you able to isolate that into a test case that I can run myself to take a look? Edson 2010/4/12 Ade Timi <adeyinka.timi(a)nathean.com&gt; This is precisely how I expect it to be expressed. When I express in this way I get this error message: BuildError: Unable to create Field Extractor for 'loanToValue' of '[ClassObjectType class=com.nathean.rules.IndividualDecision]' in rule 'G2 Equity in Asset' even though it is a variable in my IndividualDecision class. I have 3 other rule files that have expression in this simple manner and they produce no errors and are fine. But for this, It only lets me use eval or have something like this: *rule* "G2 Equity in Asset" *ruleflow-group* "goods" *when* $d : IndividualDecision() Individual($d.loanToValue < 85.0) *then* … //System.out.println((Double.valueOf("85")).doubleValue()); System.out.println("loanToValue: " + ($d.getLoanToValue())); *End* I understand that it is pointless having that 2nd line in the when section, but it’s the only way it picks up the variables in the IndividualDecision class with no errors. I don’t know why I can’t do this with this particular rules file. I am using Eclipse. Could there be some drools configuration issue with this file? -A ------------------------------ *From:* rules-users-bounces(a)lists.jboss.org [mailto: rules-users-bounces(a)lists.jboss.org] *On Behalf Of *Wolfgang Laun *Sent:* 12 April 2010 14:30 *To:* Rules Users List *Subject:* Re: [rules-users] Double Handling Well, then drop the dialect "mvel" and write the pattern as $d : IndividualDecision( loanToVal < 85.0 ) There's no visible need to use mvel. Or eval: the simplest form for constraints is always best. -W 2010/4/12 Ade Timi <adeyinka.timi(a)nathean.com&gt; Many thanks for the response! Yes it fires when I use 85.0 instead, but it obviously shouldn’t as the condition is false. My code now looks like this: *rule* "G2 Equity in Asset" *ruleflow-group* "goods" *dialect* "mvel" *when* $d : IndividualDecision(*eval*($d.getLoanToValue() < 85.0)) *then* $d.setGoodCount($d.incGoodCount()); $d.setMessage("0065: G2: Good: Good Equity in Deal"); //System.out.println((Double.valueOf("85")).doubleValue()); System.out.println("loanToValue: " + ($d.getLoanToValue())); *end* I still get the print output of 92000.0, which is as I expect but I don’t expect the rule to be fired at all. The weird thing is that when I change the condition to ‘>’ which is the true condition it never fires! I’m at a loss as to why this is happening. - Ade ------------------------------ *From:* rules-users-bounces(a)lists.jboss.org [mailto: rules-users-bounces(a)lists.jboss.org] *On Behalf Of *Wolfgang Laun *Sent:* 11 April 2010 09:11 *To:* Rules Users List *Subject:* Re: [rules-users] Double Handling You are comparing a double to a String ("85"). Although MVEL might convert strings to numbers, I wouldn't use this without some cogent reason. Do you have this unexpected firing also when you use a double literal, i.e., 85.0 ? -W 2010/4/9 Ade Timi <adeyinka.timi(a)nathean.com&gt; Hi, I am new to Drools. I am having a problem comparing 2 double values. I have a Java class with a double attribute called loanToValue. The loanToValue is been read from an XML file and the value is 92000.0. Based on this value I do not expect this rule to be fired, but for some reason it does. And the print statement returns 92000.0. Does anyone know what I’m doing wrong? My rule looks as follows: *rule* "G2 Equity in Asset" *ruleflow-group* "goods" *dialect* "mvel" *when* $d : IndividualDecision() Individual(*eval*($d.getLoanToValue() < "85")) *then* System.out.println("loanToValue: " + ($d.getLoanToValue())); *end* * * Thanks, Ade *Adeyinka Timi* | Technical Supprt | *Nathean Technologies Ltd* Registered Office 3 Lyncon Court, IDA Science & Technology Park, Snugborough Road, Blanchardstown, Dublin 15, Ireland *T +353 1 685 3001* | VOIP 076 615 1117 | *E adeyinka.timi(a)nathean.com* | <http://www.nathean.com/>www.nathean.com Incorporated in Ireland, No. 339972 The information appearing in this email and any files transmitted with it is confidential and may not be reproduced, modified, distributed, transmitted, displayed, published or broadcast without the prior written permission of Nathean Technologies Ltd. It is intended solely for the use of the addressee(s). Nathean Technologies Ltd, its directors, officers and employees do not accept liability for any loss or damage of any nature howsoever arising pertaining to the use of information appearing in this email and/or any files transmitted with it. Whilst this email has been checked for the presence of computer viruses, Nathean Technologies Ltd does not, except as required by law, represent, warrant and/or guarantee that the integrity of this communication has been maintained nor that the communication is free of errors, viruses, interception or interference. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ 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 by Red Hat @ www.jboss.com _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

Thanks guys for your responses. This should be as simple as it gets, which adds to my frustration. See the following code below: *Java classes:* *Individual* – *public* *class* Individual { *private double assetCost;* * * *public* *void* setAssetCost(*double* assetCost) { *this*.assetCost = assetCost; } *public* *double* getAssetCost() { *return* assetCost; } } *IndividualDecision* – *public* *class* IndividualDecision { *private double loanToValue;* * * *public* *void* setLoanToValue(*double* LoanToValue) { *this*.loanToValue = LoanToValue; } *public* *double* getLoanToValue() { *return* loanToValue; } *public* *void* calcValues(Individual ind){ *this*.loanToValue = ind.getAssetCost(); } } *Rule Resourse – * * **import* com...Individual *import* com...IndividualDecision *rule* "G2 Equity in Asset" *when* $d : IndividualDecision(loanToValue() < 85.0) *then* System.out.println("loanToValue: " + ($d.getLoanToValue())); *End*