Here's the write code block:
Dataset dataset =
TDBFactory.createDataset(baseDir + "/" + projName);
dataset.begin(ReadWrite.WRITE);
Model defModel = dataset.getDefaultModel();
defModel.setNsPrefix("", SemanticStoreService.BASE_URI + projName
+ "/");
OntModel project =
ModelFactory
.createOntologyModel(OntModelSpec.OWL_DL_MEM_RULE_INF);
defModel.add(project);
OntModel projMeta =
ModelFactory
.createOntologyModel(OntModelSpec.OWL_DL_MEM_RULE_INF);
projMeta.setNsPrefix("", SemanticStoreService.BASE_URI);
dataset.addNamedModel("metadata", projMeta);
OntModel projOnt =
ModelFactory
.createOntologyModel(OntModelSpec.OWL_DL_MEM_RULE_INF);
projOnt.setNsPrefix("", SemanticStoreService.BASE_URI + projName
+ "/");
dataset.addNamedModel("ontology", projOnt);
dataset.commit();
dataset.end();
It doesn't seem to set the NsPrefix even when I supposedly set it on the
default model. Here's the fragment where I get the model and print the
namespace:
Dataset dataset =
dir.exists() ? TDBFactory.createDataset(directory) : null;
Model model = null;
dataset.begin(ReadWrite.WRITE);
model =
(modelName == null) ? dataset.getDefaultModel() : dataset
.getNamedModel(modelName);
System.out.println("Read model " + projName + " " + modelName
+ " baseURI=" + model.getNsPrefixURI(""));
The model.getNsPrefixURI returns null for all three graphs (default, ontology,
and metadata).
-----Original Message-----
From: Andy Seaborne [mailto:[email protected]]
Sent: Thursday, January 16, 2014 1:48 PM
To: [email protected]
Subject: Re: Another Problem: can't set default graph
On 16/01/14 18:40, Ed Swing wrote:
> I made the change below, and now I notice that the setNsPrefix() method
> doesn't seem to work. More specifically, when I later retrieve the stored
> model, getNsPrefix("") returns null.
Model.add does not copy prefixes.
You'll need to set them on the model for the default graph of the dataset.
Andy
>
> -----Original Message-----
> From: Andy Seaborne [mailto:[email protected]]
> Sent: Thursday, January 16, 2014 1:16 PM
> To: [email protected]
> Subject: Re: Another Problem: can't set default graph
>
> On 16/01/14 17:55, Ed Swing wrote:
>> Onto another problem...
>>
>> File dir = new File(baseDir + "/" + projName);
>> if (!dir.exists()) {
>> dir.mkdirs();s
>> Dataset dataset =
>> TDBFactory.createDataset(baseDir + "/" + projName);
>
> The dataset now exists.
>
>> dataset.begin(ReadWrite.WRITE);
>> OntModel project =
>> ModelFactory
>> .createOntologyModel(OntModelSpec.OWL_DL_MEM_RULE_INF);
>> model.setNsPrefix("", SemanticStoreService.BASE_URI + projName
>> + "/");
>> dataset.setDefaultModel(project);
>
> Same issue - a dataset in TDB is not something you flip graphs on - they have
> to be copied in and out because they are bytes on disk (+caching).
>
> The default graph is already there. You need to add to it.
>
> dataset.getDefaultModel().add(project);
>
>>
>> throws the following exception:
>> Exception in thread "main" java.lang.UnsupportedOperationException: Can't
>> set default graph via GraphStore on a TDB-backed dataset
>> at
>> com.hp.hpl.jena.tdb.store.DatasetGraphTDB.setDefaultGraph(DatasetGraphTDB.java:314)
>> at
>> com.hp.hpl.jena.sparql.core.DatasetGraphTrackActive.setDefaultGraph(DatasetGraphTrackActive.java:115)
>> at
>> com.hp.hpl.jena.sparql.core.DatasetImpl.setDefaultModel(DatasetImpl.java:215)
>> at
>> com.sas.store.service.SemanticStoreService.createProject(SemanticStore
>> Service.java:203)
>>
>> I'm not sure what's going on here. How would you set the default graph of a
>> newly created dataset? Note that this code is for the case when the dataset
>> does not exist yet.
>>
>> On a side note, it might be nice to add a method for
>> TDBFactory.createDataset(File dir)...
>
> Fore now, you can use:
> TDBFactory.createDataset(dir.getAbsolutePath()) ;
>
>>
>>
>> Edward Swing
>> Applied Research Technologist
>> Vision Systems + Technology, Inc., a SAS Company
>> 6021 University Boulevard * Suite 360 * Ellicott City * Maryland *
>> 21043
>> Tel: 410.418.5555 Ext: 919 * Fax: 410.418.8580
>> Email: [email protected]<mailto:[email protected]>
>> Web: http://www.vsticorp.com<http://www.vsticorp.com/>
>>
>>
>
>
>
