我有一个在 TopBraid 中加载的 RDF 文件,我还从 Web 导入了一些 RDF 文件。最后,我保存了基本文件并检查其代码以确保它包含导入语句。
<owl:Ontology rdf:about="">
<owl:imports rdf:resource="http://www.bbc.co.uk/nature/life/Bird"/>
<owl:imports rdf:resource="http://www.bbc.co.uk/nature/life/Animal"/>
<owl:imports rdf:resource="http://www.bbc.co.uk/nature/life/Chordate"/>
<owl:imports rdf:resource="http://www.bbc.co.uk/nature/kingdom"/>
</owl:Ontology>
所以,这就是文件,当我执行下面的 sparql 时,我得到了结果:
PREFIX wo:<http://purl.org/ontology/wo/>
SELECT *
WHERE {
?subject wo:kingdom ?object .
}
但是,当我使用与 Jena 相同的文件时,我没有得到任何结果,似乎 Jena 没有考虑导入:
// Open the bloggers RDF graph from the filesystem
InputStream in = new FileInputStream(new File("/home/noor/TBCMEWorkspace/bbc/index.rdf"));
// Create an empty in-memory model and populate it from the graph
Model model = ModelFactory.createMemModelMaker().createFreshModel();
model.read(in,null); // null base URI, since model URIs are absolute
in.close();
// Create a new query
String queryString = "PREFIX wo:<http://purl.org/ontology/wo/>" +
" SELECT * " +
" WHERE { " +
" ?subject ?x ?object . " +
" } ";
Query query = QueryFactory.create(queryString);
// Execute the query and obtain results
QueryExecution qe = QueryExecutionFactory.create(query, model);
ResultSet results = qe.execSelect();
// Output query results
ResultSetFormatter.out(System.out, results, query);
// Important - free up resources used running the query
qe.close();
有没有办法让耶拿考虑进口?