I'm trying to implement this interface BaseRDFTripleModel
<http://art.uniroma2.it/owlart/documentation/apidocs/it/uniroma2/art/owlart/models/BaseRDFTripleModel.html>
which
has a method called listNamespaces(). The Sesame implementation of this
method is achieved by simply calling the getNamespaces() method of
RepositoryConnection class. I was looking for something similar to Sesame
implementation which could be done using Jena. I haven't written nothing
yet.

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2016-03-04 2:28 GMT+01:00 A. Soroka <[email protected]>:

> The class to which you refer is not a Jena type at all and has no
> connection with the Jena Graph type. The fact that the Sesame
> RepositoryConnection type understands namespace prefixes in no way implies
> that any particular Jena type will do the same thing in the same way. I’m
> not sure there is any Jena type that could even be said to represent the
> same abstraction as a Sesame Repository or RepositoryConnection. They're
> two different and entirely independent software projects.
>
> Can you give us something of the code you are trying to write? I have a
> feeling that there is some kind of earlier misunderstanding here that is
> leading to you trying to use both Jena and Sesame types together in this
> way.
>
> ---
> A. Soroka
> The University of Virginia Library
>
> > On Mar 3, 2016, at 8:16 PM, Valerio Belcastro <
> [email protected]> wrote:
> >
> > I want to achieve the same behavior of getNamespaces()
> > <
> http://rdf4j.org/sesame/2.7/apidocs/org/openrdf/repository/RepositoryConnection.html#getNamespaces()
> >
> > method
> > from Sesame RepositoryConnection
> > <
> http://rdf4j.org/sesame/2.7/apidocs/org/openrdf/repository/RepositoryConnection.html
> >
> > class. This method returns associations between prefixes and namespaces.
> > Here is an output example:
> >
> > :: http://example.org/book/
> > ns :: http://example.org/ns#
> > vcard :: http://www.w3.org/2001/vcard-rdf/3.0#
> > dc :: http://purl.org/dc/elements/1.1/
> >
> > I know that i can retrieve all namespaces from a Jena model using
> > listNameSpaces() method, but I also need prefixes (like example above)
> >
> > 2016-03-04 0:33 GMT+01:00 A. Soroka <[email protected]>:
> >
> >> Yes, this was my point: a SPARQL (RDF) dataset is not a syntactic
> >> construct. It is a collection of graphs defined by its behavior.
> >>
> >> If you could write some more about your use case for this mechanism, we
> >> might be able to help you resolve it by some other means…
> >>
> >> ---
> >> A. Soroka
> >> The University of Virginia Library
> >>
> >>> On Mar 3, 2016, at 6:27 PM, Martynas Jusevičius <[email protected]
> >
> >> wrote:
> >>>
> >>> As far as I understand, prefix mapping is only available after
> >>> parsing, as it's a purely syntactic thing. Some syntaxes have prefixes
> >>> (Turtle or RDF/XML, for example), some don't (N-Triples). So in
> >>> general you cannot retrieve them, as there is no such thing in the RDF
> >>> data model. I might be wrong though :)
> >>>
> >>> On Fri, Mar 4, 2016 at 12:22 AM, Valerio Belcastro
> >>> <[email protected]> wrote:
> >>>> Jena Graph class has the method getPrefixMapping()
> >>>> <
> >>
> https://jena.apache.org/documentation/javadoc/jena/org/apache/jena/graph/Graph.html#getPrefixMapping--
> >>> .
> >>>> This method returns a map that associates prefixes to their uri. I
> would
> >>>> like to achieve the same behaviour with a remote graph without using
> >>>> DatasetAccessor.
> >>>>
> >>>> 2016-03-03 23:12 GMT+01:00 A. Soroka <[email protected]>:
> >>>>
> >>>>> If you are talking about a graph accessed via SPARQL, it’s not clear
> >> (to
> >>>>> me) what you mean by “prefix mapping”. A SPARQL dataset doesn’t have
> a
> >>>>> prefix mapping that is constant between queries. Is there something
> >> else
> >>>>> you mean by the term?
> >>>>>
> >>>>> ---
> >>>>> A. Soroka
> >>>>> The University of Virginia Library
> >>>>>
> >>>>>> On Mar 3, 2016, at 4:00 PM, Valerio Belcastro <
> >>>>> [email protected]> wrote:
> >>>>>>
> >>>>>> Hi guys,
> >>>>>>
> >>>>>> Is it possible to get prefix mapping from remote graph in Jena?
> >>>>>>
> >>>>>> I know that I can get a model (and then its prefix mapping) through
> >>>>>> DatasetAccessor class, but I think it is too much expensive when
> >> using a
> >>>>>> model containing large amounts of triples. Is there another way to
> >>>>> achieve
> >>>>>> this or am I missing something?
> >>>>>>
> >>>>>> thank you in advance
> >>>>>
> >>>>>
> >>
> >>
>
>

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