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= Ontology Adapter: RDFSJena =

Developer: [mailto:endres@dfki.uni-kl.de Björn Endres]

== Description ==
This adapter simply provides access to RDFS ontologies, using the HP Jena Framework.

== Characteristics ==
 * The adapter uses the Jena built-in RDFS reasoning to calculate a inference model upon intialisation. Depending on the model, this might be costy.
 * All resources within the RDF or RDFS namespace are not considered parts of the model.
 * The adapter caches every return value after the first calculation. Thus it should be quite performant but does not properly react on model changes. However, since PhaseLibs ontologies are considered immutable, this does match the specifications.
 * The {{{getName[]}}} method of all ontologie entities will return the object of an arbitrary RDFS:Label statement. If there is no such statement, the local name of the resource ist returned.


== Evaluation/Performance ==
n/a

== Specification ==
=== Intitialisation ===
The ontology adapter class is
 {{{de.dfki.km.phaselib.adapters.rdfsJena.RDFSJenaOntology}}}

In order to initialise it, you will have to provide the ontology's URI, and either
 * a Jena model object, containing the model, or
 * an [http://java.sun.com/j2se/1.3/docs/api/java/io/InputStream.html InputStream] to read a model from. This is performed by Jena itself, so every file format that is supported by the Jena framework should do.

=== Parameters ===
none

=== Dependencies ===
Needs the [http://jena.sourceforge.net/index.html Jena Project], version 2.0 or higher.

== License Issues ==
Jena is an open source project featuring it's own [http://jena.sourceforge.net/license.html license].