ViSta:: a tool suite for the visualization of behavioral requirements

ViSta is a tool suite designed to support the requirements specification phase of reactive systems. It enables the user to prepare and analyze a diagrammatic description of requirements using the statechart notation. ViSta includes a template wizard, a graphical editor and a statechart visualization tool. The template wizard guides the user through the steps necessary for the extraction of relevant information from a textual description of requirements. This information is stored in a database that is used by the statechart visualization tool to automatically generate statechart layouts. The statechart visualization tool offers a Framework that combines hierarchical drawing, labeling, and floorplanning techniques. Hence, the automatically produced drawings enjoy several important aesthetic properties: they emphasize the natural hierarchical decomposition of states into substates; they have a low number of edge crossings; they have a good aspect ratio, and require a small area. These aesthetic features are invaluable since they allow the user to shift focus from organizing the mental or physical structure of the requirements document to its analysis. (C) 2001 Elsevier Science Inc. All rights reserved.