Applying UML and Patterns: An Introduction to Object-Oriented Analysis and Design and Iterative Development, Third Edition

Chapter 31. Domain Model Refinement

	Crude classifications and false generalizations are the curse of the organized life.
	--A generalization by H.G. Wells

Objectives

• Refine the domain model with generalizations, specializations, association classes, time intervals, composition, and packages.

• Identify when showing a subclass is worthwhile.

Introduction

Generalization and specialization are fundamental concepts in domain modeling that support an economy of expression; further, conceptual class hierarchies are often the basis of inspiration for software class hierarchies that exploit inheritance and reduce duplication of code. Association classes capture information about an association itself. Time intervals capture the important concept that some business ...