Hi Marco, On Mon, 2011-05-16 at 19:46 +0200, Marco Seysse wrote: > Dear Jena community, > > While reading the documentation and class diagramms of the Jena OWL API I > figured out to need more information to understand the context. > > My idea is to search in an OWL-DL ontology for related concepts of one or > more given concepts. Since SPARQL just works on RDF level I see just a chance > to achieve this by jumping from concept to concept via their relations.
What to you mean by "their relations" in this case? OWL concepts are related by things like rdfs:subClassOf relations. Are those the ones you are trying to follow? If so the OntAPI provides that straightforwardly. > Could you offer me some explanation and/or code examples how it is possible > to make it work? There are code examples in the OntAPI documentation: http://jena.sourceforge.net/ontology/ In order to give you more specific pointers we would need a bit more detail on what you are trying to do. > Or do you know other approaches how to perform semantic searches in an OWL-DL > ontology? The term "semantic search" means many different things to different people :) Again if you could explain what you are trying to do then someone might be able to offer suggestions. > My second question is about the exact purpose of the “Graph” interface and > its relation to the “Model” interface. Does “Graph” interface stand for one > rdf graph and “Model” for the whole collection of linked RDF graphs in an > ontology? No. Graphs (and the corresponding Node and Triple classes) are internal constructs. They provide an SPI to make it easier for people implementing backend stores. The Graph interface is very simple to make it easy to implement, doesn't provide any convenience functions and is not limited to the RDF syntactic constraints on which parts of a triple can be a literal or bNode. Models (and the corresponding RDFNode/Resource/Literal and Statement classes) are the normal API that most users should use. A Model is implemented internally by pointing at a Graph but provides a rather large number of convenience methods to make it easier to manipulate and query. Dave
