[rules-users] NullPointerException with factType.get(fact, "fieldname")

[JarkkoMakela]

Drools version 6.0.0.FINAL

I create rule package in Drools workbench and use default knowledgebase and
session:

 KieServices kieServices = KieServices.Factory.get();
    KieContainer kContainer =
kieServices.newKieContainer(kieServices.newReleaseId("com.test",
"validationrules", "1.0-SNAPSHOT"));
    
    KieBase kbase = kContainer.getKieBase();
    KieSession ksession = kContainer.newKieSession();

I have a query that returns ValidationError:

query "getValidationErrors"
validationError: ValidationError()
end

ValidationError is returned and it has values in its fields, but when i try
to read fields of that ValidationError fact, i get NullPointerException

public class DroolsValidationMessage {
  private FactType factType;
  private Object fact;

  public DroolsValidationMessage(KieBase kbase, Object fact) {
    this.fact = fact;
    factType = kbase.getFactType(fact.getClass().getPackage().getName(),
fact.getClass().getSimpleName());
    }

  public String getSeverity() {
    return (String) factType.get(fact, "severity");     //  <--
java.lang.NullPointerException
}

  public String getDescription() {
    return  (String) factType.get(fact, "description");
  }
}

factType looks like this:
ClassDefinition{className='null', superClass='java.lang.Object',
interfaces=[], definedClass=class com.test.validationrules.ValidationError,
traitable=null, abstract=false,
fields={description=FieldDefinition{name='description',
type='java.lang.String', key=false, inherited=false, index=0,
initExpr='null', annotations=null, accessor=null},
severity=FieldDefinition{name='severity', type='java.lang.String',
key=false, inherited=false, index=1, initExpr='null', annotations=null,
accessor=null}


This works if the rules and declared class is in resources folder and
kmodule.xml is used.

    KieServices kieServices = KieServices.Factory.get();
    KieContainer kContainer = kieServices.getKieClasspathContainer();
    KieBase kbase = kContainer.getKieBase("kbase");
    KieSession ksession = kContainer.newKieSession("ksession");


factType looks like this:
ClassDefinition{className='com.test.validationrules.ValidationError',
superClass='java.lang.Object', interfaces=[java.io.Serializable],
definedClass=class com.test.validationrules.ValidationError, traitable=NONE,
abstract=false, fields={description=FieldDefinition{name='description',
type='java.lang.String', key=false, inherited=false, index=0,
initExpr='null', annotations=null, accessor=[ClassFieldExtractor
class=com.test.validationrules.ValidationError field=description]},
severity=FieldDefinition{name='severity', type='java.lang.String',
key=false, inherited=false, index=1, initExpr='null', annotations=null,
accessor=[ClassFieldExtractor class=com.test.validationrules.ValidationError
field=severity]}

-Jarkko



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