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Posted to users@jena.apache.org by wk <de...@bass-impact.com> on 2014/04/15 21:53:05 UTC
jena api - typos and TDB
hello,
i found some typos at the following site:
http://jena.apache.org/documentation/tdb/java_api.html#constructing-a-model-or-dataset
instead of ReadeWrite.READ or ReadeWrite.WRITE it should be ReadWrite....
however, im trying to use TDB, is this the appropriate tool to combine
several rdf files to be able to query them all at the same time?
best,
walt
Re: jena api - typos and TDB
Posted by Andy Seaborne <an...@apache.org>.
On 15/04/14 20:53, wk wrote:
> hello,
>
> i found some typos at the following site:
>
> http://jena.apache.org/documentation/tdb/java_api.html#constructing-a-model-or-dataset
>
> instead of ReadeWrite.READ or ReadeWrite.WRITE it should be ReadWrite....
Thanks - fixes done on the staging site.
Andy
Re: Fwd: Re: jena api - typos and TDB
Posted by wk <de...@bass-impact.com>.
thank you for your tipps, will try them out right away!
best,
Walt
On 04/18/2014 05:10 PM, Joshua TAYLOR wrote:
> On Tue, Apr 15, 2014 at 7:08 PM, wk <de...@bass-impact.com> wrote:
>> ok, i think i got it. funny thing is, i found your stackoverflow answer to a similar question.
>> so i basically did the following:
>>
>> model = ModelFactory.createDefaultModel();
>> File dir = new File(directory);
>> File[] directoryListing = dir.listFiles();
>> if (directoryListing != null) {
>> for (File child : directoryListing) {
>> if(child.toString().endsWith("rdf") || child.toString().endsWith("RDF")) {
>> Model m = ModelFactory.createDefaultModel().read(child.toString());
>> model.add( m );
>> }
>> }
>> }
>>
>> then without saving i use the model to perform my queries at. this should be it, shouldn't it?
> I don't know that
>
>> if(child.toString().endsWith("rdf") || child.toString().endsWith("RDF")) {
> is quite as robust as it could be; there are other common extensions
> for files that have RDF content. In RDF/XML serialization, you'll
> typically see .rdf or .owl (when it's an RDF/XML serialization of an
> OWL ontology), but there's also N3/Turtle (.n3, .ttl), and N-Triples
> (.nt). Even if you only want things ending with .rdf, it'd probably
> be more sensible to the getName() method, and you consider normalizing
> the case and checking against that:
>
> child.getName().toLowerCase().endsWith("rdf");
> otherwise, you'd miss things like .RdF, .rDF, etc. Also, you don't
> need to create a new model for each file, since the model.add( m )
> call is just taking the triples from m and adding them to model. You
> can just do
>
> for ( File child : directoryListing ) {
> if ( child.getName().toLowerCase().endsWith("rdf") ) {
> model.read( child.getAbsolutePath() );
> }
> }
>
> //JT
>
>> On 04/15/2014 10:22 PM, wk wrote:
>>
>> sorry, i forgot to reply to the full list.
>>
>>
>> -------- Original Message --------
>> Subject: Re: jena api - typos and TDB
>> Date: Tue, 15 Apr 2014 22:20:02 +0200
>> From: wk <de...@bass-impact.com>
>> To: users@jena.apache.org
>>
>>
>> hello Joshua,
>>
>> thx for reply. i really need some help here.
>> the context is the following. i need to build a RESTful service where
>> someone can upload RDF files and then query the information. the upload
>> is already implemented, now i need to be able to query those RDF files
>> (all in one folder) programatically through the jena api. i already
>> managed to query one specific RDF file successfully, however i need to
>> implement the case where i don't know exactly the number and the name of
>> these RDF files which should all be in one folder. is this information
>> helpful?
>>
>> best regards,
>> Walt
>>
>> On 04/15/2014 10:11 PM, Joshua TAYLOR wrote:
>>> On Tue, Apr 15, 2014 at 3:53 PM, wk <de...@bass-impact.com> wrote:
>>>> however, im trying to use TDB, is this the appropriate tool to combine
>>>> several rdf files to be able to query them all at the same time?
>>> This is a rather broad question, and I think you'll need to provide a
>>> bit more context. In one sense, the easiest way to combine a bunch of
>>> RDF graphs and execute SPARQL queries over them would be to use Jena's
>>> rdfcat command line utility to combine them, and Jena's sparql command
>>> line utility to execute the queries. Some more context will help to
>>> determine what's a good fit for your situation, though.
>>>
>>
>>
>>
>
>
Re: Fwd: Re: jena api - typos and TDB
Posted by Joshua TAYLOR <jo...@gmail.com>.
On Tue, Apr 15, 2014 at 7:08 PM, wk <de...@bass-impact.com> wrote:
>
> ok, i think i got it. funny thing is, i found your stackoverflow answer to a similar question.
> so i basically did the following:
>
> model = ModelFactory.createDefaultModel();
> File dir = new File(directory);
> File[] directoryListing = dir.listFiles();
> if (directoryListing != null) {
> for (File child : directoryListing) {
> if(child.toString().endsWith("rdf") || child.toString().endsWith("RDF")) {
> Model m = ModelFactory.createDefaultModel().read(child.toString());
> model.add( m );
> }
> }
> }
>
> then without saving i use the model to perform my queries at. this should be it, shouldn't it?
I don't know that
> if(child.toString().endsWith("rdf") || child.toString().endsWith("RDF")) {
is quite as robust as it could be; there are other common extensions
for files that have RDF content. In RDF/XML serialization, you'll
typically see .rdf or .owl (when it's an RDF/XML serialization of an
OWL ontology), but there's also N3/Turtle (.n3, .ttl), and N-Triples
(.nt). Even if you only want things ending with .rdf, it'd probably
be more sensible to the getName() method, and you consider normalizing
the case and checking against that:
child.getName().toLowerCase().endsWith("rdf");
otherwise, you'd miss things like .RdF, .rDF, etc. Also, you don't
need to create a new model for each file, since the model.add( m )
call is just taking the triples from m and adding them to model. You
can just do
for ( File child : directoryListing ) {
if ( child.getName().toLowerCase().endsWith("rdf") ) {
model.read( child.getAbsolutePath() );
}
}
//JT
>
> On 04/15/2014 10:22 PM, wk wrote:
>
> sorry, i forgot to reply to the full list.
>
>
> -------- Original Message --------
> Subject: Re: jena api - typos and TDB
> Date: Tue, 15 Apr 2014 22:20:02 +0200
> From: wk <de...@bass-impact.com>
> To: users@jena.apache.org
>
>
> hello Joshua,
>
> thx for reply. i really need some help here.
> the context is the following. i need to build a RESTful service where
> someone can upload RDF files and then query the information. the upload
> is already implemented, now i need to be able to query those RDF files
> (all in one folder) programatically through the jena api. i already
> managed to query one specific RDF file successfully, however i need to
> implement the case where i don't know exactly the number and the name of
> these RDF files which should all be in one folder. is this information
> helpful?
>
> best regards,
> Walt
>
> On 04/15/2014 10:11 PM, Joshua TAYLOR wrote:
> > On Tue, Apr 15, 2014 at 3:53 PM, wk <de...@bass-impact.com> wrote:
> >> however, im trying to use TDB, is this the appropriate tool to combine
> >> several rdf files to be able to query them all at the same time?
> >
> > This is a rather broad question, and I think you'll need to provide a
> > bit more context. In one sense, the easiest way to combine a bunch of
> > RDF graphs and execute SPARQL queries over them would be to use Jena's
> > rdfcat command line utility to combine them, and Jena's sparql command
> > line utility to execute the queries. Some more context will help to
> > determine what's a good fit for your situation, though.
> >
>
>
>
>
--
Joshua Taylor, http://www.cs.rpi.edu/~tayloj/
Re: jena api - typos and TDB
Posted by wk <de...@bass-impact.com>.
hello Joshua,
thx for reply. i really need some help here.
the context is the following. i need to build a RESTful service where
someone can upload RDF files and then query the information. the upload
is already implemented, now i need to be able to query those RDF files
(all in one folder) programatically through the jena api. i already
managed to query one specific RDF file successfully, however i need to
implement the case where i don't know exactly the number and the name of
these RDF files which should all be in one folder. is this information
helpful?
best regards,
Walt
On 04/15/2014 10:11 PM, Joshua TAYLOR wrote:
> On Tue, Apr 15, 2014 at 3:53 PM, wk <de...@bass-impact.com> wrote:
>> however, im trying to use TDB, is this the appropriate tool to combine
>> several rdf files to be able to query them all at the same time?
>
> This is a rather broad question, and I think you'll need to provide a
> bit more context. In one sense, the easiest way to combine a bunch of
> RDF graphs and execute SPARQL queries over them would be to use Jena's
> rdfcat command line utility to combine them, and Jena's sparql command
> line utility to execute the queries. Some more context will help to
> determine what's a good fit for your situation, though.
>
Re: jena api - typos and TDB
Posted by Joshua TAYLOR <jo...@gmail.com>.
On Tue, Apr 15, 2014 at 3:53 PM, wk <de...@bass-impact.com> wrote:
> however, im trying to use TDB, is this the appropriate tool to combine
> several rdf files to be able to query them all at the same time?
This is a rather broad question, and I think you'll need to provide a
bit more context. In one sense, the easiest way to combine a bunch of
RDF graphs and execute SPARQL queries over them would be to use Jena's
rdfcat command line utility to combine them, and Jena's sparql command
line utility to execute the queries. Some more context will help to
determine what's a good fit for your situation, though.
--
Joshua Taylor, http://www.cs.rpi.edu/~tayloj/