  The object-oriented class is, in general, the most utilized element in
programming and modeling. It is employed throughout the software development
process, from early domain analysis phases to later maintenance phases. A class
diagram typically uses elements of graph theory, e.g., boxes, ovals, lines.
Many researchers have examined the class diagram layout from different
perspectives, including visibility, juxtaposability, and aesthetics. While
software systems can be incredibly complex, class diagrams represent a very
broad picture of the system as a whole. The key to understanding of such
complexity is use of tools such as diagrams at various levels of
representation. This paper develops a more elaborate diagrammatic description
of the class diagram that includes flows of attributes, thus providing a basic
representation for specifying behavior and control instead of merely listing
methods.
