Gentlepeople, I am fairly new to Drools and have what I hope is a simple question.

attempting to marshal (serialize) a Drools knowledge session and then unmarshall it. The marshalling works but the unmarshalling fails with

null pointer exception. The error is apparently with unmarshalling a global variable in the session. The session is created from a spreadsheet (decision table). This spreadsheet has two RuleTables. The first of these exists solely so that I can

some constants into the session, specifically the name and price of the

the spreadsheet is dealing with. The second ruletable is where the rules

specified. The exception occurs when unmarshalling the first rule in

first rule table. If, as a test, I eliminate the first rule table, then I

successfully marshal and unmarshall the session. The marshalling is done using the following, simplified, code: Marshaller marshaller = MarshallerFactory.newMarshaller(kbase); File droolsSessionFile = new File(MARSHAL_FILE); foStream = new FileOutputStream(droolsSessionFile); baos = new ByteArrayOutputStream(); marshaller.marshall(baos, ksession); baos.writeTo(foStream); and the unmarshalling is done like this: Marshaller marshaller = MarshallerFactory.newMarshaller(pricingProcessor.getKnowledgeBase()); FileInputStream fis = new FileInputStream(MARSHAL_FILE); StatefulKnowledgeSession ksession = marshaller.unmarshall(fis); So, where did I go wrong? Perhaps I need to deal with the global

differently, perhaps by putting it in the knowledgeBase before I

the session? Thank you for any help. Alex Ormond -- View this message in context:

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Thanks for the response. The first rule table in the spreadsheet (kinda) looks like this: RuleTable Constants NAME CONDITION ACTION ACTION eval(! productPricer.isConstantsSet($1) ) productPricer.setConstant($1, $2); productPricer.setConstantsSet($1); Rule Name Set? ProductName TRUE "NAME", "Champion CL" DefaultCost TRUE "COST", "80000" DefaultPrice TRUE "PRICE", "100000" DefaultLength TRUE "LENGTH", "53" Done TRUE TRUE The first rule generated looks like this: rule "ProductName" when eval(! productPricer.isConstantsSet() ) then productPricer.setConstant("NAME", "Champion CL"); end Alex -----Original Message----- From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Wolfgang Laun Sent: Monday, January 07, 2013 11:22 AM To: Rules Users List Subject: Re: [rules-users] unmarshal global variable The crucial info is: what is in the first table, how do you insert this data? Is it a DRL global? A fact? How does the (generated) rule look like? -W On 07/01/2013, acormond <acormond(a)greatdanetrailers.com&gt; wrote: > Gentlepeople, > > I am fairly new to Drools and have what I hope is a simple question. I am > attempting to marshal (serialize) a Drools knowledge session and then > unmarshall it. The marshalling works but the unmarshalling fails with a > null pointer exception. The error is apparently with unmarshalling a > global > variable in the session. > > The session is created from a spreadsheet (decision table). This > spreadsheet > has two RuleTables. The first of these exists solely so that I can enter > some > constants into the session, specifically the name and price of the product > the > spreadsheet is dealing with. The second ruletable is where the rules are > specified. The exception occurs when unmarshalling the first rule in the > first > rule table. If, as a test, I eliminate the first rule table, then I can > successfully marshal and unmarshall the session. > > The marshalling is done using the following, simplified, code: > > Marshaller marshaller = MarshallerFactory.newMarshaller(kbase); > File droolsSessionFile = new File(MARSHAL_FILE); > foStream = new FileOutputStream(droolsSessionFile); > baos = new ByteArrayOutputStream(); > marshaller.marshall(baos, ksession); > baos.writeTo(foStream); > > and the unmarshalling is done like this: > > Marshaller marshaller = > MarshallerFactory.newMarshaller(pricingProcessor.getKnowledgeBase()); > FileInputStream fis = new FileInputStream(MARSHAL_FILE); > StatefulKnowledgeSession ksession = marshaller.unmarshall(fis); > > > So, where did I go wrong? Perhaps I need to deal with the global variable > differently, perhaps by putting it in the knowledgeBase before I unmarshall > the session? > > Thank you for any help. > > Alex Ormond > > > > > -- > View this message in context: > http://drools.46999.n3.nabble.com/unmarshal-global-variable-tp4021375.ht ml > Sent from the Drools: User forum mailing list archive at Nabble.com. > _______________________________________________ > 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

Many thanks to all who responded. Wolfgang, I assume you provided the answer. Thank you, I'll give it a shot. Yes, the rule works separate of marshalling. I can believe there's a better way to get constants into the session from a spreadsheet, but this is the only way I could get to work. Yes, I did declare "variables" in the spreadsheet. Cheers to all, Alex -----Original Message----- From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Wolfgang Laun Sent: Monday, January 07, 2013 12:44 PM To: Rules Users List Subject: Re: [rules-users] unmarshal global variable A DRL global is not marshalled /unmarshalled along with the session. You'll have to marshal/unmarshal this object separately, and setGlobal it again in the restored session. -W On 07/01/2013, Ormond, Alex C. (GDLP) <ACOrmond(a)greatdanetrailers.com&gt; wrote: > Thanks for the response. The first rule table in the spreadsheet > (kinda) looks like this: > > RuleTable Constants > NAME CONDITION ACTION ACTION > > eval(! productPricer.isConstantsSet($1) ) > productPricer.setConstant($1, $2); > productPricer.setConstantsSet($1); > Rule Name Set? > ProductName TRUE "NAME", "Champion CL" > DefaultCost TRUE "COST", "80000" > DefaultPrice TRUE "PRICE", "100000" > DefaultLength TRUE "LENGTH", "53" > Done TRUE TRUE > > > The first rule generated looks like this: > > rule "ProductName" > when > eval(! productPricer.isConstantsSet() ) > then > productPricer.setConstant("NAME", "Champion CL"); > end > > > Alex > > > -----Original Message----- > From: rules-users-bounces(a)lists.jboss.org > [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Wolfgang Laun > Sent: Monday, January 07, 2013 11:22 AM > To: Rules Users List > Subject: Re: [rules-users] unmarshal global variable > > The crucial info is: what is in the first table, how do you insert this > data? > Is it a DRL global? A fact? How does the (generated) rule look like? > -W > > On 07/01/2013, acormond <acormond(a)greatdanetrailers.com&gt; wrote: >> Gentlepeople, >> >> I am fairly new to Drools and have what I hope is a simple question. > I am >> attempting to marshal (serialize) a Drools knowledge session and then >> unmarshall it. The marshalling works but the unmarshalling fails with > a >> null pointer exception. The error is apparently with unmarshalling a >> global >> variable in the session. >> >> The session is created from a spreadsheet (decision table). This >> spreadsheet >> has two RuleTables. The first of these exists solely so that I can > enter >> some >> constants into the session, specifically the name and price of the > product >> the >> spreadsheet is dealing with. The second ruletable is where the rules > are >> specified. The exception occurs when unmarshalling the first rule in > the >> first >> rule table. If, as a test, I eliminate the first rule table, then I > can >> successfully marshal and unmarshall the session. >> >> The marshalling is done using the following, simplified, code: >> >> Marshaller marshaller = MarshallerFactory.newMarshaller(kbase); >> File droolsSessionFile = new File(MARSHAL_FILE); >> foStream = new FileOutputStream(droolsSessionFile); >> baos = new ByteArrayOutputStream(); >> marshaller.marshall(baos, ksession); >> baos.writeTo(foStream); >> >> and the unmarshalling is done like this: >> >> Marshaller marshaller = >> MarshallerFactory.newMarshaller(pricingProcessor.getKnowledgeBase()); >> FileInputStream fis = new FileInputStream(MARSHAL_FILE); >> StatefulKnowledgeSession ksession = marshaller.unmarshall(fis); >> >> >> So, where did I go wrong? Perhaps I need to deal with the global > variable >> differently, perhaps by putting it in the knowledgeBase before I > unmarshall >> the session? >> >> Thank you for any help. >> >> Alex Ormond >> >> >> >> >> -- >> View this message in context: >> > http://drools.46999.n3.nabble.com/unmarshal-global-variable-tp4021375.ht > ml >> Sent from the Drools: User forum mailing list archive at Nabble.com. >> _______________________________________________ >> 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 > _______________________________________________ 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