Visualization and Graphical Layout in Object - Oriented Systems ∗ Volker Haarslev

This report describes a new approach to visualizing program systems within the objectoriented paradigm. This approach is based on a TEX-like notation which has been extended and generalized for specifying graphical layout of arbitrary objects. Our simplest scheme offers specifications similar to TEX’s box-and-glue metaphor. Size and position of boxes and glue can be specified by constraints. The CLOS meta-level architecture is used to associate visualization and application objects. We propose several useful techniques such as indirect values, slot and method demons, and instance-specific meta-objects. Our techniques require no modifications to the systems which are selected for visualization. We demonstrate the feasibility of our approach using application domains such as CLOS debugging and constraint systems. ∗ This report combines and extends the following two papers: A Declarative Formalism for Specifying Graphical Layout, published in: Proceedings, 1990 IEEE Workshop on Visual Languages, Skokie/IL, Oct. 4-6, 1990, IEEE Computer Society Press, 1990. A Framework for Visualizing Object-Oriented Systems, published in: Proceedings, ECOOP/OOPSLA’90, European Conference on Object-Oriented Programming and Object Oriented Programming: Systems, Languages and Applications, Oct. 21-25, 1990, Ottawa/Canada, ACM Sigplan Notices, 1990.