The geoviz toolkit: using component-oriented coordination methods for geographic visualization and analysis

In this paper, we present the GeoViz Toolkit (GVT), an open-source, Internet-delivered program for geographic visualization and analysis that features a diverse set of software components which can be flexibly combined by users who do not have programming expertise. The design and architecture of the GVT allows us to address three key research challenges in geovisualization: allowing end users to create their own geovisualization and analysis component set on the fly, integrating geovisualization methods with spatial analysis methods, and making geovisualization applications sharable between users. Each of these tasks necessitates a robust yet flexible approach to intertool coordination. The coordination strategy developed for the GVT, called Introspective Observer Coordination, leverages and combines key advances in software engineering from the last decade, such as automatic introspection of objects, software design patterns, and reflective invocation of methods.