JUNG also provides a visualization

JUNG also provides a visualization framework that makes it easy to construct tools for the interactive exploration of network data. Users can use one of the layout algorithms provided, or use the framework to create their own custom layouts. In addition, filtering mechanisms are provided which allow users to focus their attention, or their algorithms, on specific portions of the graph.
As an open-source library, JUNG provides a common framework for graph/network analysis and visualization. We hope that JUNG will make it easier for those who work with relational data to make use of one anothers' development efforts, and thus avoid continually re-inventing the wheel.