Hi Andy,
After trying what you told me, I'm able now to load a file with quads. But
now it's impossible to copy the content from one Dataset to another one,
here what I'm trying to do :
VirtDataset vd = new VirtDataset("jdbc:virtuoso://localhost:1111", "dba",
"dba");
DatasetGraph vdg = vd.asDatasetGraph();
DatasetGraph dg = RDFDataMgr.loadDatasetGraph("data.nq", Lang.NQUADS);
Iterator<Node> nodeIt = dg.listGraphNodes();
while (nodeIt.hasNext()) {
Node node = nodeIt.next();
Graph graph = dg.getGraph(node);
vdg.addGraph(node, graph);
}
RDFDataMgr.write(System.out, vdg, RDFFormat.NQUADS_UTF8);
When I try to write the final DatasetGraph, I have this exception :
Exception in thread "main" java.lang.UnsupportedOperationException: subject
cannot be null
at com.hp.hpl.jena.graph.Triple.<init>(Triple.java:38)
at
virtuoso.jena.driver.VirtDataset$VirtDataSetGraph.find(VirtDataset.java:497)
at org.apache.jena.riot.writer.NQuadsWriter.write(NQuadsWriter.java:91)
at org.apache.jena.riot.RDFDataMgr.write$(RDFDataMgr.java:1274)
at org.apache.jena.riot.RDFDataMgr.write(RDFDataMgr.java:1148)
at
fr.eurecom.cixty.privacytest.PrivacyDeployment.addData(PrivacyDeployment.java:265)
at
fr.eurecom.cixty.privacytest.PrivacyDeployment.main(PrivacyDeployment.java:81)
I also tried this code :
VirtDataset vd = new VirtDataset("jdbc:virtuoso://localhost:1111", "dba",
"dba");
RDFDataMgr.read(vd.asDatasetGraph(),
Files.newInputStream(Paths.get("data.nq")), Lang.NQUADS);
But the same exception occurs.
Anything I did wrongly ?
Best.
-------------------------------------------------------------------------------------------------------------------------------
Julien Plu
PhD Student at Eurecom.
Personal webpage: http://jplu.developpez.com
FOAF file : http://jplu.developpez.com/julien
Email address : [email protected]
Phone : +33493008200
Twitter : @julienplu
2014-07-13 2:34 GMT+02:00 Julien Plu <[email protected]>:
> Ok thank you !
>
> I will try with a dataset now.
>
>
> -------------------------------------------------------------------------------------------------------------------------------
> Julien Plu
>
> PhD Student at Eurecom.
> Personal webpage: http://jplu.developpez.com
> FOAF file : http://jplu.developpez.com/julien
> Email address : [email protected]
> Phone : +33493008200
> Twitter : @julienplu
>
>
> 2014-07-12 19:48 GMT+02:00 Andy Seaborne <[email protected]>:
>
> On 11/07/14 15:31, Julien Plu wrote:
>>
>>> Hi,
>>>
>>> I try to read a N-QUAD file to load it in a model but unfortunalety
>>> nothing
>>> is loaded. Here what I do :
>>>
>>> Model m = RDFDataMgr.loadModel("data.nq", Lang.NQUADS);
>>> RDFDataMgr.write(System.out, m, RDFFormat.NQUADS_UTF8);
>>>
>>> At the end nothing is displayed on the console. And I have just one line
>>> inside my file :
>>>
>>> <http://example.com/Toto> <http://xmlns.com/foaf/0.1/name> "Toto" <
>>> http://example.com> .
>>>
>>> Do-I something wrong ? Or is-there another way to do that ?
>>>
>>> Thanks in advance for your answer.
>>>
>>> Best.
>>>
>>> Julien.
>>>
>>>
>> A model is a single graph. It can't hold named graphs.
>>
>> If you read N-quads (default and named graphs) into a Model (a single
>> graph) only the default graph goes into the model.
>>
>> Use a dataset to get the set of all graphs in the n-quads files.
>>
>> Andy
>>
>
>
