jena

问题 In Jena there are some default ontologies like RDF, FOAF... So we can add property to resource like: resource.addProperty(FOAF.name, person.getMFirstName()); But I need another ontology that does not exist in Jena like SIOC, pimo that I have the URI for. How can I do this? 回答1: Jena has a tool for generating Java classes that contain the constants from ontologies and RDF schemas: schemagen 来源： https://stackoverflow.com/questions/5979747/how-to-add-vocabulary-in-jena

问题 I've been searching for a solution for days now and since there is no forum at Apache Jena I had to create an account at stackoverflow to ask. My problem is that I need a temporary (deep) copy of an already loaded ontology, namely an object of OntModelImpl (with some imports but without any attached inference machine). Its purpose is to apply some validation steps on the model which require some SPARQL UPDATE queries to add some automatically generated triples first. These additional triples

问题 I have two separate Jena models, one containing an RDFS ontology and the other containing the statements. Right now I cannot, for example, write a query which returns all results for a particular class, since the class is not described in the RDF statements. What I want is to query the statements model by taking into account the ontology as well. How can I do this? 回答1: You can query the ontology using SPARQL language and store the result and you can query other statements using any normal

问题 I have two separate Jena models, one containing an RDFS ontology and the other containing the statements. Right now I cannot, for example, write a query which returns all results for a particular class, since the class is not described in the RDF statements. What I want is to query the statements model by taking into account the ontology as well. How can I do this? 回答1: You can query the ontology using SPARQL language and store the result and you can query other statements using any normal

问题 I have two separate Jena models, one containing an RDFS ontology and the other containing the statements. Right now I cannot, for example, write a query which returns all results for a particular class, since the class is not described in the RDF statements. What I want is to query the statements model by taking into account the ontology as well. How can I do this? 回答1: You can query the ontology using SPARQL language and store the result and you can query other statements using any normal

问题 I have two separate Jena models, one containing an RDFS ontology and the other containing the statements. Right now I cannot, for example, write a query which returns all results for a particular class, since the class is not described in the RDF statements. What I want is to query the statements model by taking into account the ontology as well. How can I do this? 回答1: You can query the ontology using SPARQL language and store the result and you can query other statements using any normal

问题 I have two separate Jena models, one containing an RDFS ontology and the other containing the statements. Right now I cannot, for example, write a query which returns all results for a particular class, since the class is not described in the RDF statements. What I want is to query the statements model by taking into account the ontology as well. How can I do this? 回答1: You can query the ontology using SPARQL language and store the result and you can query other statements using any normal

问题 I have two separate Jena models, one containing an RDFS ontology and the other containing the statements. Right now I cannot, for example, write a query which returns all results for a particular class, since the class is not described in the RDF statements. What I want is to query the statements model by taking into account the ontology as well. How can I do this? 回答1: You can query the ontology using SPARQL language and store the result and you can query other statements using any normal

问题 I'm doing a parser from a csv file that builds an RDF. Right now it just adds as property the header of the csv and it's value. When I try to write the output as XML I get this error: Caused by: org.apache.jena.shared.BadURIException: Only well-formed absolute URIrefs can be included in RDF/XML output: <A> Code: 57/REQUIRED_COMPONENT_MISSING in SCHEME: A component that is required by the scheme is missing. But when I write it as json I get correct output. Does anyone know what I have wrong?

问题 When issuing a SPARQL CONSTRUCT query to a specific endpoint, Apache Jena library 3.14.0 issues an error message as follows. Endpoint returned Content Type: application/sparql-results+xml which is not a valid RDF syntax The code I wrote is as follows. QueryEngineHTTP qeh = new QueryEngineHTTP(endpointUrl, rq); qeh.setAcceptHeader("application/rdf+xml"); Model m = qeh.execConstruct(); The endpoint is https://id.nlm.nih.gov/mesh/sparql . The query is as follows. CONSTRUCT {?s <http://id.nlm.nih