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

Chapter 11. Operation Contracts

	When ideas fail, words come in very handy.
	--Johann Wolfgang von Goethe

Objectives

• Define system operations.

• Create contracts for system operations.

Introduction

Use cases or system features are the main ways in the UP to describe system behavior, and are usually sufficient. Sometimes a more detailed or precise description of system behavior has value. Operation contracts use a pre- and post-condition form to describe detailed changes to objects in a domain model, as the result of a system operation. A domain model is the most common OOA model, but operation contracts and state models (introduced on p. 485) can also be useful OOA-related artifacts.

Operation contracts may be considered part of the UP Use-Case Model ...