CODEWITHSUNDEEP
javasparqlowl-api
MS1
MS1

Reputation: 518

owlapi HERMIT and SPARQL

How is it possible to execute a SPARQL Query in Java using the HERMIT reasoner 1.3.8? I'm using owlapi 4.2 and i have loaded the HERMIT reasoner using:

OWLReasonerFactory reasonerFactory = new Reasoner.ReasonerFactory();
OWLReasoner reasonerHermit = reasonerFactory.createReasoner(ontology);

Unfortunately i could not find any explanation how to execute a SPARQL Query with this reasoner?! Is this possible at all? If not, what other possibilities (other reasoners) do i have using owlapi and SPARQL?

EDIT:

I now know that i need a SPARQL Engine. This is why i used SPARQL-DL like this:

QueryEngine engine = QueryEngine.create(manager, reasoner, true);
Query query = Query.create("...");
QueryResult result = engine.execute(query);
System.out.println(result);

The query works, but if I'm now getting something like 

?de.derivo.sparqldlapi.Var@69 = http://www.example.com/project1#document_1

how do i get out the http://www.example.com/project1#document_1? I could not find a proper Method for getting this value.

Upvotes: 0

Views: 741

Answers (2)

Ignazio
Ignazio

Reputation: 10659

Looking at the source for QueryResult, available here, what you have there is a query binding. You have methods to iterate over all the bindings, and you should find the value you are after in the bound values of the binding.

Upvotes: 2

UninformedUser
UninformedUser

Reputation: 8465

HermiT is an OWL reasoner and not a SPARQL engine. There is an API called SPARQL-DL, but according to its website it supports just OWL API v3.x. A newer forked version with OWL API 4 support can be found as part of the Protege project: https://github.com/protegeproject/sparql-dl-api

Upvotes: 3

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