Read OWL Instances in form of rdf:Description question

[Evangelia Daskalaki <ev...@ics.forth.gr>]

Dear all,
I have an OWL file which I read by using the jena API.
At the moment I read all the Classes ( model.listClasses() ) ,  the 
Objectproperties (model.listObjectProperties() ) ,  the 
Datatypeproperties (model.listDatatypeProperties() ) and the Individuals 
(model.listIndividuals()).
But the OWL file contains also Individuals expressed in the form of 
rdf:Description:

Example:
<rdf:Description rdf:about="#7700574884352544358">
<hasDataValue rdf:datatype="&xsd;string">Rachel Rath</hasDataValue>
</rdf:Description>

How can I read these individuals?

Thank you in advance,
Eva


-- 
---------------------------------------------
	
Evangelia Daskalaki							
	Information System Laboratory			
	Institute of Computer Science			
	Foundation of Research&  Technology	
	e-mail: eva@ics.forth.gr				
	Tel: 0030 2810391623 						
										
	Ευαγγελία Δασκαλάκη					
	Εργαστήριο Πληροφοριακών Συστημάτων	
	Ινστιτούτο Πληροφορικής				
	Ίδρυμα Τεχνολογίας&  Έρευνας			
	e-mail: eva@ics.forth.gr				
	Tηλ: 0030 2810391623 						
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Re: Read OWL Instances in form of rdf:Description question

[Evangelia Daskalaki <ev...@ics.forth.gr>]

Thank you Dave for you corrections and the solutions you offered.

I have used the listStatements( null, EG.hasDataValue, (RDFNode)null)  
and it works fine.


Kind Regards,
Eva


Στις 9/8/2011 7:52 PM, ο/η Dave Reynolds έγραψε:
> On Thu, 2011-09-08 at 13:48 +0300, Evangelia Daskalaki wrote:
>> Dear all,
>> I have an OWL file which I read by using the jena API.
>> At the moment I read all the Classes ( model.listClasses() ) ,  the
>> Objectproperties (model.listObjectProperties() ) ,  the
>> Datatypeproperties (model.listDatatypeProperties() ) and the Individuals
>> (model.listIndividuals()).
> [Probably just use of language but the "read" step is when you load the
> data into your Model. All those list* API calls are then queries onto
> that model, they aren't literally reading the file.]
>
>> But the OWL file contains also Individuals expressed in the form of
>> rdf:Description:
>>
>> Example:
>> <rdf:Description rdf:about="#7700574884352544358">
>> <hasDataValue rdf:datatype="&xsd;string">Rachel Rath</hasDataValue>
>> </rdf:Description>
>>
>> How can I read these individuals?
> Depends what it is about those that identify them.
>
> You could use:
>
>     listSubjectsWithProperty( EG.hasDataValue )
>
> or (nearly equivalent)
>
>     listStatements( null, EG.hasDataValue, (RDFNode)null)
>
> Alternatively if your ontology defines a domain for hasDataValue then
> you could turn on inference (OWLMicro) and those would then become
> identifiable as individuals.
>
> Dave
>
>
>

Re: Read OWL Instances in form of rdf:Description question

[Dave Reynolds <da...@gmail.com>]

On Thu, 2011-09-08 at 13:48 +0300, Evangelia Daskalaki wrote: 
> Dear all,
> I have an OWL file which I read by using the jena API.
> At the moment I read all the Classes ( model.listClasses() ) ,  the 
> Objectproperties (model.listObjectProperties() ) ,  the 
> Datatypeproperties (model.listDatatypeProperties() ) and the Individuals 
> (model.listIndividuals()).

[Probably just use of language but the "read" step is when you load the
data into your Model. All those list* API calls are then queries onto
that model, they aren't literally reading the file.]

> But the OWL file contains also Individuals expressed in the form of 
> rdf:Description:
> 
> Example:
> <rdf:Description rdf:about="#7700574884352544358">
> <hasDataValue rdf:datatype="&xsd;string">Rachel Rath</hasDataValue>
> </rdf:Description>
> 
> How can I read these individuals?

Depends what it is about those that identify them.

You could use:

   listSubjectsWithProperty( EG.hasDataValue )

or (nearly equivalent)

   listStatements( null, EG.hasDataValue, (RDFNode)null)

Alternatively if your ontology defines a domain for hasDataValue then
you could turn on inference (OWLMicro) and those would then become
identifiable as individuals.

Dave