Graphical Notations for Rule Modeling

This chapter describes various graphical notations for rule modeling. Rule modeling methodologies, empowered with graphical notations, play an important role in helping business experts and rule engineers to represent business rules formally for further deployment into a rule execution system. Rules, represented graphically, can be easier understood by business people and by technicians without intensive technical learning. In this chapter we mainly focus on three graphical notations for rules: UML/OCL, URML and ORM. UML/OCL is a mainstream modeling technology in software development, which is also accommodated by some business experts when modeling a system at the semi-formal, platform independent level. URML extends UML with additional graphical symbols and the concept of a rule, which allows visualization of different rule types on top of UML class diagrams. ORM is an alternative methodology with a rich graphical notation for modeling a domain at the conceptual level. The methodological power, graphical expressivity, and verbalization capabilities of ORM have made it the most popular language within the business rules community. This chapter introduces each of these graphical notations, explain how it can be used, and compare them against each other.