Semantic Web Programming

Appendix E. Jena Reference Guide

The programming examples in this Appendix use the Jena Semantic Web Framework. This reference guide contains two parts: the key Jena classes and the main programming steps for using the Jena Semantic Web Framework.

The first part contains the key classes and presents them in alphabetic order. The second part contains the main Jena programming steps and presents them in life-cycle order.

Note

The Jena class descriptions are adapted from the Javadocs that are available in the downloaded Jena zip file. The Javadocs also contain additional details regarding associated classes, methods, and parameters.

Key Jena Classes

The following sections describe the key Jena classes.

DIGReasoner Class

This reasoner is the generator of inference graphs (InfGraph) that can use an external DIG inference engine to perform DL reasoning tasks.

bind(), bindSchema() binds a given graph to the external reasoner.

configure() configures reasoner properties.

DIGReasonerFactory Class

This is a factory class for generating instances of DIG reasoners. It implements the singleton pattern.

create() creates a DIG reasoner.

Graph Interface

This is the interface that must be satisfied by implementations maintaining collections of RDF triples. The core interface is small (add, delete, find, contains) and is augmented by additional classes to handle more complicated matters such as reification, query handling, bulk update, event management, and transaction handling. It enables alternate persistence ...