Chapter 3. RDF Model

Table of Contents

3.1. Package org.openrdf.model.impl

Figure 3.1. Class diagram for the RDF model

Class diagram for the RDF model

The class diagram above shows the interfaces that are defined in Sesame's RDF Model, package org.openrdf.model. The RDF entities "URI", "blank node" and "literal" are organized in a hierarchy reflecting their use in RDF. The interfaces Value and Resource are empty place holders to make this hierachical organization possible. These place holders are also used in the Statement interface to reference the appropriate set of value types for the subject and object.

Various implementations of the RDF Model interfaces are possible. For example, a Sail implementation might have its own dedicated implementation that adds Sail-specific functionality. The ValueFactory interface allows one to transparently create any of these objects. Every Sail is able to produce a ValueFactory object that can be used for this purpose.

3.1. Package org.openrdf.model.impl

Package org.openrdf.model.impl contains a default implementation of the RDF Model interfaces. These classes can be used by Sail implementations that have no need for their own implementation. The classes are also useful when operating outside the context of a Sail object, for example when using Rio as a separate library.