Page 102 - DCAP308_OBJECT_ORIENTED_ANALYSIS_AND_DESIGN

Object Oriented Analysis and Design Anil Sharma,Lovely Professional University

Notes Unit 8: Advanced Interaction Modelling

CONTENTS
Objectives

Introduction
8.1 Use Case Relationships
8.1.1 Communicates

8.1.2 Extends
8.1.3 Include or Uses
8.1.4 Generalization
8.2 Procedural Sequence Models

8.2.1 Sequence Diagrams with Passive Objects
8.2.2 Sequence Diagrams with Transient Objects

8.2.3 Guidelines for Procedural Sequence Models
8.3 Special Constructs for Activity Models
8.3.1 Conditional Threads
8.3.2 Nested Activity Diagram

8.4 Summary
8.5 Keywords
8.6 Review Questions

8.7 Further Readings

Objectives

After studying this unit, you will be able to:
Define use case relationships

Discuss the concept of sequence diagrams with passive objects
Describe the concept of sequence diagrams with transient objects
Explain the special constructs for activity models

Introduction

Interactions can be modeled at different levels of abstraction. At a higher level use cases describe
how a system interacts with outside actors. Each use case represents a piece of functionality that
a system provides to its users. Use cases are helpful for capturing informal software requirements.
Sequence diagrams provide more details and show the messages exchanged among a set of
object over time. Message includes both asynchronous signals and procedure call. They are
good for showing the behavior sequences seen by users of a system. Finally, activity diagrams
provide further details and show the flow of control among the steps of computation. In this

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