Recursion in rules execution

[tarandeep.singh]

Hi,

I've below rules in my rule file, when i execute this drl, it leads to recursion when rules are fired. It'll be really great if somebody can suggest what can be done to avoid recursion during execution of dynamic rules given below.

package com.globallogic.rules
import com.thirdpillar.QuoteUpdater
import java.lang.String
import java.math.BigDecimal

global BigDecimal TEMP
global BigDecimal GL_SD_Amt

rule "gst_rate_ol"
 no-loop true
 salience 50
 when
 QuoteUpdater:QuoteUpdater()
 eval(QuoteUpdater.getCustomerTypeCountry().equals("New Zealand") &&
 QuoteUpdater.isFinanceLease() == true ||
 QuoteUpdater.isRental() == true ||
 QuoteUpdater.isOperatingLease() == true ||
 QuoteUpdater.isHirePurchase() == true)
 then
 System.out.println("1");
 TEMP = BigDecimal . valueOf ( 0.125 ) ;
 QuoteUpdater . setQuoteLevelGSTRate ( BigDecimal . valueOf ( TEMP . doubleValue ( ) ) ) ;
 modify(QuoteUpdater);
end
rule "NZ_SD"
 no-loop true
 salience 45
 when
 QuoteUpdater:QuoteUpdater()
 eval(QuoteUpdater . getCustomerTypeCountry ( ).equals("New Zealand"))
 then
 System.out.println("2");
 QuoteUpdater . setQuoteLevelGSTStreamRate ( BigDecimal . valueOf ( 0 ) ) ;
 QuoteUpdater . setQuoteLevelStampDutyRate ( BigDecimal . valueOf ( 0 ) ) ;
 GL_SD_Amt = BigDecimal . valueOf ( 0 ) ;
 QuoteUpdater . setQuoteLevelStampDutyAmount ( BigDecimal . valueOf ( 0 ) ) ;
 modify(QuoteUpdater);
end
rule "gst_stream_rate_ol"
 salience 40
 no-loop true
 when
 QuoteUpdater:QuoteUpdater()
 eval(QuoteUpdater.getCustomerTypeCountry().equals("New Zealand") &&
 QuoteUpdater.isRental() == true ||
 QuoteUpdater.isOperatingLease() == true)
 then
 System.out.println("3");
 TEMP = BigDecimal . valueOf ( 0.125 ) ;
 QuoteUpdater . setQuoteLevelGSTStreamRate ( BigDecimal . valueOf ( TEMP . doubleValue ( ) ) ) ;
 modify(QuoteUpdater);
end

code in my test class is given below.

 /**
 *
 */
package com.thirdpillar;

import java.io.InputStreamReader;
import java.io.Reader;

import org.drools.RuleBase;
import org.drools.RuleBaseFactory;
import org.drools.WorkingMemory;
import org.drools.compiler.PackageBuilder;
import org.drools.rule.Package;

/**
 * @author tarun.singh
 *
 */
public class BasedOnDynamic {

 /**
 * @param args
 */
 public static void main(String[] args) {
 try {
 QuoteUpdater quoteUpdater = new QuoteUpdater();
 quoteUpdater.setCustomerTypeCountry("New Zealand");
 quoteUpdater.setFinanceLease(true);
 quoteUpdater.setRental(true);
 quoteUpdater.setOperatingLease(true);
 quoteUpdater.setHirePurchase(true);

 final Reader source = new InputStreamReader( QuoteUpdater.class.getResourceAsStream( "BasedOnDynamic.drl" ) );
 final PackageBuilder builder = new PackageBuilder();
 builder.addPackageFromDrl( source );
 final Package pkg = builder.getPackage();
 final RuleBase ruleBase = RuleBaseFactory.newRuleBase();
 ruleBase.addPackage( pkg );

 final WorkingMemory workingMemory = ruleBase.newWorkingMemory();
 workingMemory.assertObject( quoteUpdater );
 workingMemory.fireAllRules();

 } catch (Exception e) {
 e.printStackTrace();
 }
 }

}

[vivonpereira]

You have to be very careful while using the 'OR' condition (||) in the JBoss rules.
In the documentation that the JBoss have provided, they do mention that, every OR will be treated as a seperate sub-rule by itself.
Hence, if u have a rule like this: condition1 || condition2, then the result is going to be executed twice for the two specified conditions.

Hence, i recommend u judiciously use the or condition.
Bcoz, if u have a condition like the one below, then the result would be totally wrong:
rule test
when
t:Test(age > 25 || skill == 'IT')
then
t.setWage(t.getWage() * 1000);
end

The result should have been 1000 but it would give 1000000.

There is one more point I have noticed in ur rule file is that, there are more than one rule containing modify method. When I wrote my rule file, it did not allow me to have more than one non-exclusive rule to have a modify method.
Could u tell me, didnt it throw u any error. Since it hangs my code when it finds two rules having modify method in the same drl file.
The java code is the same as urs.

[kranthidalai]

i am new to drools, i gone through drools documentation, now we are drools in our project as semantic module frame work as java. so can i have the details of how to write new drl file and java file in eclipse IDE(drools IDE) and what are the required JAR file for that.

[kranthidalai]

i am new to drools, i gone through drools documentation, now we are drools in our project as semantic module frame work as java. so can i have the details of how to write new drl file and java file in eclipse IDE(drools IDE) and what are the required JAR file for that.

[kranthidalai]

i am new to drools, i gone through drools documentation, now we are drools in our project as semantic module frame work as java. so can i have the details of how to write new drl file and java file in eclipse IDE(drools IDE) and what are the required JAR file for that.