Apache Jena is a free and open source Semantic Web framework for Java.
It provides an API to extract data from and write to RDF graphs. The graphs are represented as an abstract “model”. A model can be sourced with data from files, databases, URLs or a combination of these. A model can also be queried through SPARQL.
Jena is similar to RDF4J (formerly OpenRDF Sesame); though, unlike RDF4J, Jena provides support for OWL (Web Ontology Language). The framework has various internal reasoners and the Pellet reasoner (an open source Java OWL-DL reasoner) can be set up to work in Jena.
Fuseki is an HTTP interface to RDF data. It supports SPARQL for querying and updating. The project is a sub-project of Jena and is developed as a servlet. Fuseki can also be run as a stand-alone server as it ships preconfigured with the Jetty web server.
Jena supports serialisation of RDF graphs to:
- a relational database
- Notation 3