[rules-users] Please help - losing hair

[Richard Hoberman]

1. I can't find any mention of dialects anywhere in the Drools 4
manual.  Am I missing something?

2. I've tried the following after finding a snippet in the archives for
this list:

    package mvanamibia.claim;

    import java.lang.Object;
    import java.lang.String;
    import java.lang.Double;
    import java.util.Date;
    import java.util.List;
    import java.util.ArrayList;
    import com.sadalbari.mvanamibia.beans.Claim;
    import com.sadalbari.mvanamibia.beans.Mandate;
    import com.sadalbari.mvanamibia.beans.SubmissionInfo;
    import com.sadalbari.mvanamibia.inspector.ClaimEvaluation;

    global ClaimEvaluation evaluation;

    rule "hasDateReceived"
        dialect "mvel"
        when
            Claim( submissionInfo == null )
        then
            evaluation.getViolations().add("missing: date received");
    end


but it gives the following exception:

    java.lang.NullPointerException
        at
    org.drools.rule.builder.RuleBuildContext.<init>(RuleBuildContext.java:115)
        at
    org.drools.compiler.PackageBuilder.addRule(PackageBuilder.java:350)
        at
    org.drools.compiler.PackageBuilder.addPackage(PackageBuilder.java:233)
        at
    org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:157)
        at
    com.sadalbari.mvanamibia.model.UnregisteredClaimValidationTest.setupWorkingMemory(UnregisteredClaimValidationTest.java:29)
        at
    com.sadalbari.mvanamibia.model.UnregisteredClaimValidationTest.testEmptyClaim(UnregisteredClaimValidationTest.java:42)
    ... Removed 22 stack frames


Thanks

Richard


Mark Proctor wrote:
> in theory for nested accessors it should switch to the MVEL dialect
> automatically. You only need to specify the MVEL dialect explicitely
> for eval, return value and consequences.
>
> Mark
> Manjax23 wrote:
>> I think you should use dialect "mvel" when accessing the nested accessors.
>> and I had some trouble with "mvel" dialect in 4M2 release.
>>
>> Please let me know if it works for you..
>>
>> Thanks,
>> Manjax23
>>
>>
>> Richard Hoberman wrote:
>>   
>>> I'm using Drools 4 (M2), which is supposed to support nested accessors*
>>>
>>> This works: when Claim( submissionInfo == null), but not this: when
>>> Claim( submissionInfo.date == null)
>>>
>>> Rule file, SubmissionInfo.java and exception are below.
>>>
>>> What am I missing?
>>>
>>> Richard
>>>
>>>
>>>
>>>
>>> * See
>>> http://article.gmane.org/gmane.comp.java.drools.user/8079/match=nested+properties,
>>> which states "Support to nested accessors, property navigation and
>>> simplified collection, arrays and maps syntax"
>>>
>>> Rule File
>>>
>>> ---------------------------------------------------------------------------------------
>>> package mvanamibia.claim;
>>>
>>> import java.lang.Object;
>>> import java.lang.String;
>>> import java.lang.Double;
>>> import java.util.Date;
>>> import java.util.List;
>>> import java.util.ArrayList;
>>> import com.sadalbari.mvanamibia.beans.Claim;
>>> import com.sadalbari.mvanamibia.beans.Mandate;
>>> import com.sadalbari.mvanamibia.beans.SubmissionInfo;
>>> import com.sadalbari.mvanamibia.inspector.ClaimEvaluation;
>>>
>>> global ClaimEvaluation evaluation;
>>>
>>> rule "hasDateReceived"
>>>
>>>     when
>>>         Claim( submissionInfo.date == null )
>>>     then
>>>         evaluation.getFailures().add("missing: date received");
>>> end
>>>
>>> -----------------------------------------------------------------------------------
>>>
>>> Exception
>>> -----------------------------------------------------------------------------------
>>> org.drools.rule.InvalidRulePackage: [19,23]: unknown:19:23 mismatched
>>> token: [@137,471:471='.',<69>,19:23]; expecting type RIGHT_PAREN
>>>     at org.drools.rule.Package.checkValidity(Package.java:368)
>>>     at
>>> org.drools.common.AbstractRuleBase.addPackage(AbstractRuleBase.java:250)
>>>     at
>>> com.sadalbari.mvanamibia.model.UnregisteredClaimValidationTest.setupWorkingMemory(UnregisteredClaimValidationTest.java:33)
>>>     at
>>> com.sadalbari.mvanamibia.model.UnregisteredClaimValidationTest.testMandateClaim(UnregisteredClaimValidationTest.java:56)
>>> ... Removed 22 stack frames
>>> FAILED: testEmptyClaim
>>> org.drools.rule.InvalidRulePackage: [19,23]: unknown:19:23 mismatched
>>> token: [@137,471:471='.',<69>,19:23]; expecting type RIGHT_PAREN
>>>     at org.drools.rule.Package.checkValidity(Package.java:368)
>>>     at
>>> org.drools.common.AbstractRuleBase.addPackage(AbstractRuleBase.java:250)
>>>     at
>>> com.sadalbari.mvanamibia.model.UnregisteredClaimValidationTest.setupWorkingMemory(UnregisteredClaimValidationTest.java:33)
>>>     at
>>> com.sadalbari.mvanamibia.model.UnregisteredClaimValidationTest.testEmptyClaim(UnregisteredClaimValidationTest.java:42)
>>> ... Removed 22 stack frames
>>>
>>>
>>> ------------------------------------------------------
>>> SubmissionInfo (relevant bits)
>>>
>>> public class SubmissionInfo implements Serializable {
>>>
>>>     private Date date;
>>>
>>>     public Date getDate() {
>>>         return date;
>>>     }
>>>
>>>     public void setDate(Date date) {
>>>         this.date = date;
>>>     }
>>>
>>>
>>> _______________________________________________
>>> rules-users mailing list
>>> rules-users at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/rules-users
>>>
>>>
>>>     
>>
>>   
>
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