UML 2.0 in Action: A project-based tutorial: A detailed and practical walk-through showing how to apply UML to real world development projects

247 Pages·2005·9.17 MB·English

by  Patrick Graessle

UML 2.0 in Action
A Project-Based Tutorial
Patrick Grässle
Henriette Baumann
Philippe Baumann

BIRMINGHAM - MUMBAI
UML 2.0 in Action
A Project-Based Tutorial
Copyright © 2005 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system,
or transmitted in any form or by any means, without the prior written permission of the
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Every effort has been made in the preparation of this book to ensure the accuracy of the
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or distributors will be held liable for any damages caused or alleged to be caused directly
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However, Packt Publishing cannot guarantee the accuracy of this information.

First published: September 2005.

Published by Packt Publishing Ltd.
32 Lincoln Road
Olton
Birmingham, B27 6PA, UK.
ISBN 1-904811-55-8
www.packtpub.com
Cover Design by www.visionwt.com
Authorized translation from the German Edition:
"UML 2.0 projektorientiert"
© 2004 by Galileo Press
GALILEO COMPUTING is an imprint of Galileo Press,
Fort Lee, NJ (USA), Bonn (Germany).
German Edition first published 2004 by Galileo Press.
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Credits
Authors Technical Editor
Patrick Grässle Chris Smith
Henriette Baumann Paramita Chakrabarti
Philippe Baumann
Translator
Illustrators Silvia Saint-Vincent
Nilesh Mohite
Dinesh Kandalgaonkar Proofreader
Chris Smith
Cover Designer
Helen Wood Layout
Paramita Chakrabarti
Manjiri Nadkarni

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Table of Contents
About This Book 1
Chapter 1: Introduction 5
Chapter 2: Basic Principles and Background 9
2.1 Introduction to the Case Study 9
2.2 Models, Views, and Diagrams 12
2.2.1 What is a Model? 12
2.2.2 Why do we Need Models? 14
2.2.3 Purpose and Target Group of a Model 15
Practical Tips 16
2.2.4 Process of Analysis 16
Practical Tips 17
2.2.5 Diagrams as Views 18
2.3 Information Systems and IT Systems 19
2.4 The Models of our Case Study 21
2.5 History of UML: Methods and Notations 22
2.6 Requirement Specification 25
2.6.1 Guidance for Decision Making 25
2.6.2 Verification 26
2.7 UML 2.0 26
2.7.1 Overview of UML 2.0 26
2.7.2 Effects on the Business System Model 29
2.7.3 Effects on the IT System Model 29
2.7.4 Effects on the Systems Integration Model 30
2.7.5 Conclusion 30
Chapter 3: Modeling Business Systems 31
3.1 Business Processes and Business Systems 32
3.1.1 What is a Business Process? 32
3.1.2 Definition of the Workflow Management Coalition 33
3.1.3 Business Systems 34
Table of Contents
3.1.4 Using UML to Model Business Processes and Business Systems 36
3.1.5 Practical Tips for Modeling Business Processes 37
3.2 One Model—Two Views 37
3.3 External View 40
3.3.1 What Benefit does a Business System Provide? 40
Business Use Cases 41
Actors 42
3.3.2 The Elements of a View 43
3.3.3 Use Case Diagrams 45
Reading Use Case Diagrams 47
3.3.4 Constructing Use Case Diagrams 49
Collecting Information Sources—How am I Supposed to Know That? 50
Identifying Potential Actors—Which Partners and Customers Use the Goods
and Services of the Business System? 51
Identifying Potential Business Use Cases—Which Goods and Services Can
Actors Draw Upon? 52
Practical Tips 53
Connecting Business Use Cases—Who Can Make Use of What Goods
and Services of the Business System? 53
Describing Actors—Who or What do the Actors Represent? 54
Searching for More Business Use Cases—What else Needs to be Done? 54
Editing Business Use Cases—What actually has to be Included in a
Business Use Case? 55
Documenting Business Use Cases—What Happens in a Business Use Case? 56
Modeling Relationships between Business Use Cases—What Activities
are Conducted Repeatedly? 57
Verifying the View—Is Everything Correct? 57
Practical Tips 59
3.3.5 Activity Diagrams 59
Reading Activity Diagrams 65
3.3.6 Constructing Activity Diagrams 67
Collect Information Sources—How am I Supposed to Know That? 68
Find Activities and Actions—What has to be Done When Actors Draw upon
Offered Goods and Services? 68
Connect Actions—In Which Order are Actions Processed? 69
Refine Activities—Do any Other Activity Diagrams have to be Added? 70
Adopt Actors from Business Use Cases—Who is Responsible for Each Action? 71
Verify the View—Is Everything Correct? 72
3.3.7 Sequence Diagrams 72
Reading Sequence Diagrams 74
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3.3.8 Constructing Sequence Diagrams 75
Designate Actors and Business System—Who is Taking Part? 76
Designate Initiators—Who Starts Interactions? 76
Describe the Message Exchange between Actors and the
Business System—Which Messages are being Exchanged? 77
Identify the Course of Interactions—What is the Order? 77
Insert Additional Information—What Else is Important? 77
Verify the View—Is Everything Correct? 78
3.3.9 High-Level Sequence Diagrams 78
3.3.10 Sequence Diagrams for Scenarios of Business Use Cases 79
3.4 The Internal View 80
3.4.1 The Elements of the View 80
3.4.2 Package Diagram 81
Reading Package Diagrams 83
3.4.3 Constructing Package Diagrams 84
Develop an Initial Package Diagram of the Business System—Which Workers
and Business Objects Make up the Business System? 84
Find Additional Organization Units—Who Else is There? 85
Assign Workers and Business Objects to the Organization Units—Who
Belongs Where? 85
Find Additional Organization Units, Workers, or Business Objects—What
Else is There? 85
Verify the View—Is Everything Correct? 86
3.4.4 Class Diagram 87
Reading Class Diagrams 89
3.4.5 Constructing Class Diagrams 90
Find Classes—Which Classes Exist in the Class Diagram? 90
Create Associations Between Classes—Which Classes Deal with Each Other? 91
Substantiate Associations—What do these Relationships Mean? 92
Insert Generalizations—Can Business Objects be Grouped? 92
Verify the View—Is Everything Correct? 93
3.4.6 Activity Diagram 94
Reading Activity Diagrams 94
3.4.7 Constructing Activity Diagrams 94
Collect Information Sources—How am I Supposed to Know That? 94
Find Activities and Actions—Which Activities Have to be Performed so that
the Goods and Services Utilized by Actors can be Provided and Delivered? 95
Adopt Actors from Business Use Cases—Who is Responsible for Each Action? 95
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Connect Actions—In Which Order are Actions Processed? 95
Refine Activities—Do any Other Activity Diagrams Have to be Added? 96
Verify the View—Is Everything Correct? 96
Chapter 4: Modeling IT Systems 99
4.1 External View 102
4.1.1 The User View or "I don't care how it works, as long as it works." 102
4.1.2 The Elements of a View 106
4.1.3 Use Case Diagram 107
Reading Use Case Diagrams 109
4.1.4 Query Events and Mutation Events 110
4.1.5 Use Case Sequence Diagram 112
Reading Use Case Sequence Diagrams 114
4.1.6 Constructing the External View 115
Collect Information Sources—How Am I Supposed to Know That? 116
Identify Potential Actors—Who Works with the IT System? 116
Identify Potential Use Cases—What Can be Done With the IT System? 117
Connect Actors and Use Cases—Who Can Do What with the IT System? 118
Describe Actors—Who or What do the Actors Represent? 118
Search for More Use Cases—What Functionalities does the IT System
have to Provide? 119
Edit Use Cases—What Actually Has to be Included in a Use Case? 119
Document Use Cases—What Happens in a Use Case? 121
Model Relationships between Use Cases—What can be Reused? 122
Verify the View—Is Everything Correct? 123
4.2 Structural View 124
4.2.1 Objects and Classes 129
4.2.2 Generalization, Specialization, and Inheritance 128
4.2.3 Static and Dynamic Business Rules 132
4.2.4 Elements of the View 132
4.2.5 Class Diagram 133
Reading Class Diagrams 135
4.2.6 Constructing Class Diagrams 139
Identify and Model Classes—Which Classes do We Need? 140
Identify and Model Associations—How Are the Classes Connected? 141
Define Attributes—What do We Want to Know about the Objects? 142
List Required Queries and Inputs—What does the IT System Need to
Deliver and Accept? 143
Formulate Queries and Inputs—How Exactly Should the Display Look? 143
Conduct Information Analysis—Which Classes, Associations, and Attributes
do We Need? 144
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Consolidate Class Diagrams—How Does Everything Fit Together? 146
Verify the Class Diagrams—Is Everything Correct? 146
4.3 The Behavioral View 147
4.3.1 The Life of an Object 147
4.3.2. The Elements of the View 151
4.3.3 Statechart Diagram 152
Reading Statechart Diagrams 154
4.3.4 Constructing Statechart Diagrams 159
Identify Mutation Events Relevant for the Object—What Affects the Object? 159
Group Relevant Events Chronologically—How Does a Normal Life Look? 160
Model States and Transitions—Which States are There? 161
Add Actions to the Statechart Diagram—What Do Objects Do? 161
Verify Statechart Diagram—Is Everything Correct? 162
4.4 Interaction View 163
4.4.1 Seeing What Happens Inside the IT System 163
4.4.2 Elements of the View 167
4.4.3 Communication Diagram 168
Reading Communication Diagrams 170
4.4.4 Sequence Diagram 172
Reading Sequence Diagrams 174
4.4.5 Constructing Communication Diagrams 175
Draft Query Result—What do We Want? 176
Identify Involved Classes—Which Classes do We Need? 177
Define Initial Object—Where Do We Start? 179
Design Event Path—Where Do We Go? 179
Amend Event Path—Exactly Which Objects do We Need? 181
Identify Necessary Attributes—What Exactly do We Want to Know? 182
Verify the Communication Diagram—Is Everything Correct? 183
4.4.6 Constructing Sequence Diagrams 184
Identify Involved Classes—What is Affected by Mutation Events? 184
Determine Initial Object—Where does the Mutation Event go First? 185
Propagate Events—How is the Mutation Event Forwarded? 185
Specify Event Parameter—What Do Objects have to Know? 186
Verify the Sequence Diagram—Is Everything Correct? 186
Chapter 5: Modeling for System Integration 187
5.1 Terminology of System Integration 188
Interfaces 188
Messages 188
Enterprise Application Integration 189
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