Knowledge Information Systems Group, Salzburg, Austria

Salzburg Research

RDF Gravity (RDF Graph Visualization Tool)

Sunil Goyal, Rupert Westenthaler
{sgoyal, rwestenthaler}
Salzburg Research, Austria

RDF Gravity is a tool for visualising RDF/OWL Graphs/ ontologies.
Its main features are:

  • Graph Visualization
  • Global and Local Filters (enabling specific views on a graph)
  • Full text Search
  • Generating views from RDQL Queries
  • Visualising multiple RDF files

RDF Gravity is implemented by using the JUNG Graph API and Jena semantic web toolkit.

Figure 1: Screenshot of RDF-Gravity, showing a part of Wine Ontology

Main Features

1 Graph Visualisation

RDF Gravity defines a visualization package on top of the JUNG Graph API.
This package provides the following functionality:

  • Configurable renderers for edges and nodes of a graph, including different node shapes and edge decorations etc.
  • A Renderer Factory allowing the configuration of the above node and edge renderers based on the type of an edge or node.
  • Multi selection model for selection of nodes and edges of a graph.
  • Handling Mouse Events, for instance click, double click, drag, ... for nodes and edges of a graph.
  • Zooming

For graph layout, it uses the layout algorithms directly supported by the Jung API.

2 Global & Local Filters

The tool allows a user to specify Global and Local filters to have specific views on the graph.

  • Global Filters allow a user to hide or view specific edges based on type. For instance, one can hide all edges of "rdf:bag", "dc:author" or a specific type occurring in any particular given ontology.
  • Local Filters allow a user to hide or view specific particular instances of nodes or edges.
  • A user can search for concepts and can add those in the graph for visualisation.

The above functionality allows having customizable graph views on a complex graph structure.

3 Full Text Search

RDF Gravity provides a full text search over concepts, properties and instances specified in a RDF file.

4 Visualising Multiple RDF Files

RDF Gravity allows a user to view multiple graph structures contained in multiple RDF files through a single view.