> OntModel model2=ModelFactory.createOntologyModel(OntModelSpec.OWL_DL_MEM);
> InputStream in =FileManager.get().open("F://20-8.owl");
> if (in==null) {
> throw new IllegalArgumentException( "File: " + " not
> found");
> } model2.read(in,"");
>
> String ns="
> http://www.semanticweb.org/t/ontologies/2016/7/myOWL#";;
>
> OntProperty favcat=model2.getOntProperty(ns+ "BestCategory");
> String name=jTextField1.getText();
> Individual indiv = user1.createIndividual(ns + name);
> RDFNode phFav=indiv.getPropertyValue(favcat);
> if (phFav!=null){
> Literal l1=phFav.asLiteral();
If BestCategory is an object property, why do you cast the value as
literal?!
>
> s1=l1.toString(); }
> }
> if (s1=="CatPhysics"){
> JOptionPane.showMessageDialog(null, "Physics");
> }
>
> The rule itself is
>
> String rule ="[rule1: ( ?x http://www.semanticweb.org/
> t/ontologies/2016/7/myOWL#Physics_Preferred_Category ?cat1 )" +
> "( ?x http://www.semanticweb.org/t/ontologies/2016/7/myOWL#
> Chem_Preferred_Category ?cat2 )" +
> "( ?x http://www.semanticweb.org/t/ontologies/2016/7/myOWL#Geo_
> Preferred_Category ?cat3 )" +
> "greaterThan(?cat1,?cat2), greaterThan(?cat1,?cat3)"
> + " -> (?x http://www.semanticweb.org/t/
> ontologies/2016/7/myOWL#BestCategory http://www.semanticweb.org/t/
> ontologies/2016/7/myOWL#BestCategory#Physics )]";
>
>
> The BestCategory is object property.
>
> Regards
>
>
> On Tue, Jan 17, 2017 at 8:16 PM, Andy Seaborne <[email protected]> wrote:
>
>> A Complete, Minimal Example please.
>>
>>
>> Partial code, no data is not complete.
>> It must compile and run to be complete.
>>
>> Minimal means only what is necessary to ask the question not the whole
>> data or whole application.
>>
>> Andy
>>
>> On 17/01/17 17:14, Sidra shah wrote:
>>
>>> I am surprise that when there is no value in BestCategory, it gives me no
>>> error and when the rule executes and value comes in BestCategory, it gives
>>> me now *"RequiredLiteralException*"
>>>
>>> The code I used here is
>>>
>>> OntProperty favcat=model2.getOntProperty(ns+ "BestCategory");
>>>
>>> RDFNode phFav=indiv.getPropertyValue(favcat);
>>> if (phFav!=null){
>>> Literal l1=phFav.asLiteral();
>>>
>>> s1=l1.toString();}
>>>
>>> if (s1=="CatPhysics"){
>>> JOptionPane.showMessageDialog(null, "Physics");
>>> }
>>>
>>> Best regards
>>>
>>> On Tue, Jan 17, 2017 at 5:53 PM, Sidra shah <[email protected]>
>>> wrote:
>>>
>>> Hello Chris, thanks a lot for your suggestion.
>>>> Best regards.
>>>>
>>>> On Tue, Jan 17, 2017 at 5:37 PM, Chris Dollin <
>>>> [email protected]> wrote:
>>>>
>>>>
>>>>> On 17/01/17 13:30, Sidra shah wrote:
>>>>>
>>>>> Hi Lorenz, I am sorry but with much regards, you discussed here the
>>>>>> problem, not the solution :) :)
>>>>>>
>>>>>> I know this if there is no value, there must be Null exception,
>>>>>>
>>>>>>
>>>>> This is not true.
>>>>>
>>>>> but can you suggest me a way where we dodge the compiler
>>>>>
>>>>>>
>>>>> No "dodging" of the compiler is required. Instead, just write
>>>>> perfectly ordinary code that tests to see if the result of
>>>>> getPropertyValue is null, and take one action if it isn't and
>>>>> a different one if it is.
>>>>>
>>>>> There's nothing special about this. You don't need to use
>>>>> break (which is for escaping from loops); just an if
>>>>> with suitable then and else parts.
>>>>>
>>>>> I know this is more a Java problem, but any help I will appreciate.
>>>>>
>>>>>>
>>>>> Find someone /local/ doing the same or similar course and talk to
>>>>> them (and have them talk to you) about programming and this
>>>>> problem. I don't mean copy each other's work; I mean use each
>>>>> other to understand what the problem is about and how the code
>>>>> works. Each of you will know things that the other doesn't; share.
>>>>>
>>>>> Chris
>>>>>
>>>>> --
>>>>> "He could not weigh up which was worse and so tried not to think about
>>>>> either."
>>>>> /The Spellgrinder's
>>>>> Apprentice/
>>>>>
>>>>> Epimorphics Ltd, http://www.epimorphics.com
>>>>> Registered address: Court Lodge, 105 High Street, Portishead, Bristol
>>>>> BS20 6PT
>>>>> Epimorphics Ltd. is a limited company registered in England (number
>>>>> 7016688)
>>>>>
>>>>>
>>>>
--
Lorenz Bühmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center
