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Posted to users@jena.apache.org by Sidra shah <s....@gmail.com> on 2016/11/22 12:34:28 UTC
Ont Property
Does Jena have hasOntProperty() like we have hasOntClass()? In my project I
need something like if instance/individual has "this property value", do
some operation.
Thank you for your time.
Re: Ont Property
Posted by Sidra shah <s....@gmail.com>.
Thanks Lorenz for your guidance.
Best regards
On Tue, Nov 22, 2016 at 4:29 PM, Lorenz B. <
buehmann@informatik.uni-leipzig.de> wrote:
> Ok, I overlooked that you have the value given.
>
>
> > Lorenz, with regards,
> >
> > Is it mandatory to use : if( Value == null)
> No, not if you can ensure that there is always exactly one value.
> >
> > I mean every property will have a value. In my case, the property
> supposed
> > to have three values so I need:
> >
> > if (Value=="Value1")
> You have to use Java object equality instead.
> > //do this
> >
> > if (Value=="Value2")
> > //do this
> > else
> > // do this
> >
> > However, in general case, I want to ask if we have or expected to have a
> > null value, can we do some operation on it or just we display a message
> to
> > user that value is null?
> >
> > if( Value == null)
> > JOptionPane.showMessageDialog(null, "Value is null");
> You can't do anything on a NULL value - it's a Java NULL. In any case,
> you should handle this case and give a warning as you suggested.
> >
> >
> >
> >
> >
> > On Tue, Nov 22, 2016 at 3:59 PM, Lorenz B. <
> > buehmann@informatik.uni-leipzig.de> wrote:
> >
> >>
> >>> Hello Lorenz thanks,
> >>>
> >>> You mean something like this:
> >>>
> >>> RDFNode Value =individual.getPropertyValue(myPropertyName);
> >>>
> >>> if (Value=="PropertyValue")
> >> No, more the other case indeed such that don't have to "know" the value,
> >> i.e.
> >>
> >> if( Value == null) {
> >>
> >> } else {
> >>
> >> }
> >>> //
> >>>
> >>> On Tue, Nov 22, 2016 at 3:36 PM, Lorenz B. <
> >>> buehmann@informatik.uni-leipzig.de> wrote:
> >>>
> >>>> You can use Individual::getPropertyValue, see [1]
> >>>>
> >>>> [1]
> >>>> https://jena.apache.org/documentation/javadoc/jena/
> >>>> org/apache/jena/ontology/OntResource.html#
> getPropertyValue-org.apache.
> >>>> jena.rdf.model.Property-
> >>>>
> >>>>> Does Jena have hasOntProperty() like we have hasOntClass()? In my
> >>>> project I
> >>>>> need something like if instance/individual has "this property value",
> >> do
> >>>>> some operation.
> >>>>>
> >>>>> Thank you for your time.
> >>>>>
> >>>> --
> >>>> Lorenz Bühmann
> >>>> AKSW group, University of Leipzig
> >>>> Group: http://aksw.org - semantic web research center
> >>>>
> >>>>
> >> --
> >> Lorenz Bühmann
> >> AKSW group, University of Leipzig
> >> Group: http://aksw.org - semantic web research center
> >>
> >>
> --
> Lorenz Bühmann
> AKSW group, University of Leipzig
> Group: http://aksw.org - semantic web research center
>
>
Re: Ont Property
Posted by "Lorenz B." <bu...@informatik.uni-leipzig.de>.
Ok, I overlooked that you have the value given.
> Lorenz, with regards,
>
> Is it mandatory to use : if( Value == null)
No, not if you can ensure that there is always exactly one value.
>
> I mean every property will have a value. In my case, the property supposed
> to have three values so I need:
>
> if (Value=="Value1")
You have to use Java object equality instead.
> //do this
>
> if (Value=="Value2")
> //do this
> else
> // do this
>
> However, in general case, I want to ask if we have or expected to have a
> null value, can we do some operation on it or just we display a message to
> user that value is null?
>
> if( Value == null)
> JOptionPane.showMessageDialog(null, "Value is null");
You can't do anything on a NULL value - it's a Java NULL. In any case,
you should handle this case and give a warning as you suggested.
>
>
>
>
>
> On Tue, Nov 22, 2016 at 3:59 PM, Lorenz B. <
> buehmann@informatik.uni-leipzig.de> wrote:
>
>>
>>> Hello Lorenz thanks,
>>>
>>> You mean something like this:
>>>
>>> RDFNode Value =individual.getPropertyValue(myPropertyName);
>>>
>>> if (Value=="PropertyValue")
>> No, more the other case indeed such that don't have to "know" the value,
>> i.e.
>>
>> if( Value == null) {
>>
>> } else {
>>
>> }
>>> //
>>>
>>> On Tue, Nov 22, 2016 at 3:36 PM, Lorenz B. <
>>> buehmann@informatik.uni-leipzig.de> wrote:
>>>
>>>> You can use Individual::getPropertyValue, see [1]
>>>>
>>>> [1]
>>>> https://jena.apache.org/documentation/javadoc/jena/
>>>> org/apache/jena/ontology/OntResource.html#getPropertyValue-org.apache.
>>>> jena.rdf.model.Property-
>>>>
>>>>> Does Jena have hasOntProperty() like we have hasOntClass()? In my
>>>> project I
>>>>> need something like if instance/individual has "this property value",
>> do
>>>>> some operation.
>>>>>
>>>>> Thank you for your time.
>>>>>
>>>> --
>>>> Lorenz Bühmann
>>>> AKSW group, University of Leipzig
>>>> Group: http://aksw.org - semantic web research center
>>>>
>>>>
>> --
>> Lorenz Bühmann
>> AKSW group, University of Leipzig
>> Group: http://aksw.org - semantic web research center
>>
>>
--
Lorenz Bühmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center
Re: Ont Property
Posted by Sidra shah <s....@gmail.com>.
Lorenz, with regards,
Is it mandatory to use : if( Value == null)
I mean every property will have a value. In my case, the property supposed
to have three values so I need:
if (Value=="Value1")
//do this
if (Value=="Value2")
//do this
else
// do this
However, in general case, I want to ask if we have or expected to have a
null value, can we do some operation on it or just we display a message to
user that value is null?
if( Value == null)
JOptionPane.showMessageDialog(null, "Value is null");
On Tue, Nov 22, 2016 at 3:59 PM, Lorenz B. <
buehmann@informatik.uni-leipzig.de> wrote:
>
>
> > Hello Lorenz thanks,
> >
> > You mean something like this:
> >
> > RDFNode Value =individual.getPropertyValue(myPropertyName);
> >
> > if (Value=="PropertyValue")
> No, more the other case indeed such that don't have to "know" the value,
> i.e.
>
> if( Value == null) {
>
> } else {
>
> }
> > //
> >
> > On Tue, Nov 22, 2016 at 3:36 PM, Lorenz B. <
> > buehmann@informatik.uni-leipzig.de> wrote:
> >
> >> You can use Individual::getPropertyValue, see [1]
> >>
> >> [1]
> >> https://jena.apache.org/documentation/javadoc/jena/
> >> org/apache/jena/ontology/OntResource.html#getPropertyValue-org.apache.
> >> jena.rdf.model.Property-
> >>
> >>> Does Jena have hasOntProperty() like we have hasOntClass()? In my
> >> project I
> >>> need something like if instance/individual has "this property value",
> do
> >>> some operation.
> >>>
> >>> Thank you for your time.
> >>>
> >> --
> >> Lorenz Bühmann
> >> AKSW group, University of Leipzig
> >> Group: http://aksw.org - semantic web research center
> >>
> >>
> --
> Lorenz Bühmann
> AKSW group, University of Leipzig
> Group: http://aksw.org - semantic web research center
>
>
Re: Ont Property
Posted by "Lorenz B." <bu...@informatik.uni-leipzig.de>.
> Hello Lorenz thanks,
>
> You mean something like this:
>
> RDFNode Value =individual.getPropertyValue(myPropertyName);
>
> if (Value=="PropertyValue")
No, more the other case indeed such that don't have to "know" the value,
i.e.
if( Value == null) {
} else {
}
> //
>
> On Tue, Nov 22, 2016 at 3:36 PM, Lorenz B. <
> buehmann@informatik.uni-leipzig.de> wrote:
>
>> You can use Individual::getPropertyValue, see [1]
>>
>> [1]
>> https://jena.apache.org/documentation/javadoc/jena/
>> org/apache/jena/ontology/OntResource.html#getPropertyValue-org.apache.
>> jena.rdf.model.Property-
>>
>>> Does Jena have hasOntProperty() like we have hasOntClass()? In my
>> project I
>>> need something like if instance/individual has "this property value", do
>>> some operation.
>>>
>>> Thank you for your time.
>>>
>> --
>> Lorenz B�hmann
>> AKSW group, University of Leipzig
>> Group: http://aksw.org - semantic web research center
>>
>>
--
Lorenz B�hmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center
Re: Ont Property
Posted by Sidra shah <s....@gmail.com>.
Hello Lorenz thanks,
You mean something like this:
RDFNode Value =individual.getPropertyValue(myPropertyName);
if (Value=="PropertyValue")
//
On Tue, Nov 22, 2016 at 3:36 PM, Lorenz B. <
buehmann@informatik.uni-leipzig.de> wrote:
> You can use Individual::getPropertyValue, see [1]
>
> [1]
> https://jena.apache.org/documentation/javadoc/jena/
> org/apache/jena/ontology/OntResource.html#getPropertyValue-org.apache.
> jena.rdf.model.Property-
>
> > Does Jena have hasOntProperty() like we have hasOntClass()? In my
> project I
> > need something like if instance/individual has "this property value", do
> > some operation.
> >
> > Thank you for your time.
> >
> --
> Lorenz Bühmann
> AKSW group, University of Leipzig
> Group: http://aksw.org - semantic web research center
>
>
Re: Ont Property
Posted by "Lorenz B." <bu...@informatik.uni-leipzig.de>.
You can use Individual::getPropertyValue, see [1]
[1]
https://jena.apache.org/documentation/javadoc/jena/org/apache/jena/ontology/OntResource.html#getPropertyValue-org.apache.jena.rdf.model.Property-
> Does Jena have hasOntProperty() like we have hasOntClass()? In my project I
> need something like if instance/individual has "this property value", do
> some operation.
>
> Thank you for your time.
>
--
Lorenz B�hmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center