Tài liệu Object-Oriented Analysis and Design Understanding System Development with UML 2.0

1 Introduction 2
1.1 Background 4
1.2 A Brief History of Programming 4
1.3 Methodologies 5
1.4 About this Book 5
1.4.1 Content Overview 6
1.4.2 Case Studies 7
1.4.3 Navigation 7
Part I Setting the Scene 9
2 Object Concepts 10
2.1 Introduction 12
2.2 What Is an Object? 13
2.3 Identical or Equal? 16
2.4 Depicting Objects 19
2.5 Encapsulation 20
2.6 Association and Aggregation 21
2.7 Graphs and Trees 23
2.8 Links and Navigability 25
2.9 Messages 27
2.10 Invoking an Operation 28
2.11 An Example Collaboration 30
2.12 How an Object-Oriented Program Works 32
2.13 Garbage Collection 32
2.14 Classes 34
2.15 What Does a Class Define? 37
2.16 Shared Data and Shared Operations 39
2.17 Types 40
2.18 Terminology 41
2.19 Reusing Code 43
2.20 Summary 48
Further Reading 48
Review Questions 48
Answers to Activity 1 50
Answers to Review Questions 50
3 Inheritance 52
3.1 Introduction 54
3.2 Designing a Class Hierarchy 55
3.3 Adding Implementations to a Class Hierarchy 58
3.4 Abstract Classes 59
3.5 Redefining Methods 63
3.6 Implementing a Stack Class 64
3.6.1 Implementing a Stack using Inheritance 65
3.6.2 Implementing a Stack using Composition 66
3.6.3 Inheritance versus Composition 68
3.7 Multiple Inheritance 69
3.8 Guidelines for Using Inheritance 73
3.9 Summary 73
Further Reading 74
Review Questions 74
Answers to Review Questions 75
4 Type Systems 78
4.1 Introduction 80
4.2 Dynamic and Static Type Systems 80
4.3 Polymorphism 82
4.3.1 Polymorphic Variables 82
4.3.2 Polymorphic Messages 83
4.4 Dynamic Binding 85
4.5 Polymorphism Guideline 87
4.6 Type Casting 88
4.7 Explicit Casts 89
4.8 Genericity with Templates 91
4.9 Summary 93
Further Reading 93
Review Questions 93
Answers to Activity 2 95
Answers to Activity 3 95
Answers to Review Questions 96
5 Software Development Methodologies 98
5.1 Introduction 100
5.2 Classical Phases in Software Production 102
5.2.1 Requirements 102
5.2.2 Analysis 102
5.2.3 Design 103
5.2.4 Specification 103
5.2.5 Implementation 104
5.2.6 Testing 104
5.2.7 Deployment 104
5.2.8 Maintenance 104
5.2.9 Key Questions 105
5.3 Software Engineering and the Waterfall Methodology 106
5.4 New Methodologies 110
5.4.1 Spiral Methodology 110
5.4.2 Iterative Methodology 111
5.4.3 Incremental Methodology 112
5.4.4 Combining the Methodologies 113
5.5 Object-Oriented Methodologies 114
5.5.1 UML, RUP and XP 115
5.5.2 The Need for Development Tools 116
5.6 Ripple Overview 117
5.6.1 Use Case Diagram 120
5.6.2 Class Diagram (Analysis Level) 121
5.6.3 Communication Diagram 122
5.6.4 Deployment Diagram 123
5.6.5 Class Diagram (Design Level) 124
5.6.6 Sequence Diagram 125
5.7 Summary 126
Further Reading 126
Review Questions 127
Answers to Review Questions 128
Part II Understanding the Problem 129
6 Gathering Requirements 130
6.1 Introduction 132
6.2 The Birth of a System 133
6.3 Use Cases 135
6.4 Business Perspective 136
6.4.1 Identifying Business Actors 137
6.4.2 Writing the Project Glossary 138
6.4.3 Identifying Business Use Cases 139
6.4.4 Illustrating Use Cases on a Communication Diagram 141
6.4.5 Illustrating Use Cases on an Activity Diagram 143
6.5 Developer Perspective 145
6.5.1 Specializing Actors 149
6.5.2 Use Case Relationships 150
6.5.3 System Use Case Details 155
6.5.4 Preconditions, Postconditions and Inheritance 156
6.5.5 Supplementary Requirements 158
6.5.6 User Interface Sketches 158
6.5.7 Prioritizing System Use Cases 159
6.6 Summary 162
Further Reading 162
Review Questions 163
Answers to Review Questions 165
7 Analyzing the Problem 166
7.1 Introduction 168
7.2 Why Do Analysis? 168
7.3 Overview of the Analysis Process 169
7.4 Static Analysis 170
7.4.1 Finding Classes 170
7.4.2 Identifying Class Relationships 171
7.4.3 Drawing Class and Object Diagrams 172
7.4.4 Drawing Relationships 173
7.4.5 Attributes 178
7.4.6 Association Classes 182
7.4.7 Tangible versus Intangible Objects 183
7.4.8 Good Objects 188
7.5 Dynamic Analysis 188
7.5.1 Drawing Use Case Realizations 189
7.5.2 Boundaries, Controllers and Entities 191
7.5.3 Communication Diagram Elements 192
7.5.4 Adding Operations to Classes 194
7.5.5 Responsibilities 194
7.5.6 State Modeling 195
7.6 Summary 197
Further Reading 197
Review Questions 197
Answers to Activity 4 201
Answers to Review Questions 201
Part III Designing the Solution 203
8 Designing the System Architecture 204
8.1 Introduction 206
8.2 Design Priorities 207
8.3 Steps in System Design 207
8.4 Choosing a Networked System Topology 208
8.4.1 The History of Network Architectures 208
8.4.2 Three-Tier Architecture 210
8.4.3 Personal Computers 212
8.4.4 Network Computers 213
8.4.5 The Internet and the World Wide Web 214
8.4.6 Intranets 215
8.4.7 Extranets and Virtual Private Networks 215
8.4.8 Client–Server versus Distributed Architectures 216
8.4.9 Depicting Network Topology in UML 218
8.5 Designing for Concurrency 220
8.6 Designing for Security 222
8.6.1 Digital Encryption and Decryption 223
8.6.2 General Security Rules 225
8.7 Partitioning Software 225
8.7.1 Systems and Subsystems 226
8.7.2 Layers 227
8.7.3 Java Layers: Applet plus RMI 230
8.7.4 Message Flow in Layers 233
8.8 Summary 237
Further Reading 238
Review Questions 238
Answers to Review Questions 239
9 Choosing Technologies 240
9.1 Introduction 242
9.2 Client Tier Technologies 242
9.3 Client Tier to Middle Tier Protocols 244
9.4 Middle Tier Technologies 246
9.5 Middle Tier to Data Tier Technologies 247
9.6 Other Technologies 248
9.7 Typical Front-End Configurations 250
9.7.1 HTML/CGI-with-Scripts 250
9.7.2 HTML/CGI-with-Servlets 252
9.7.3 RMI 254
9.7.4 CORBA 255
9.7.5 EJB 256
9.8 Back-End Configurations 258
9.9 Java E-Commerce Configuration 258
9.10 UML Packages 262
9.11 Summary 267
Further Reading 267
Review Questions 267
Answers to Review Questions 268
10 Designing the Subsystems 270
10.1 Introduction 272
10.2 Mapping the Analysis Class Model into the Design Class Model 273
10.2.1 Mapping Operations 273
10.2.2 Variable Types 274
10.2.3 Visibility of Fields 274
10.2.4 Accessors 275
10.2.5 Mapping Classes, Attributes and Compositions 276
10.2.6 Mapping Other Types of Association 277
10.2.7 Universal Identifier 282
10.3 Handling Persistence with a Relational Database 284
10.3.1 Database Management Systems 285
10.3.2 The Relational Model 286
10.3.3 Mapping Entity Classes 288
10.3.4 Mapping Associations 289
10.3.5 Mapping Object State 292
10.4 Finalizing the User Interfaces 298
10.5 Designing the Business Services 304
10.5.1 Using Proxies and Copies 305
10.5.2 Classifying Business Services 307
10.5.3 Session Identifiers 309
10.5.4 Business Service Realization 310
10.6 Using Patterns, Frameworks and Libraries 312
10.7 Transactions 312
10.7.1 Pessimistic and Optimistic Concurrency 313
10.7.2 General Guidelines for Using Transactions with Objects 314
10.7.3 Transactions in Upper Layers 315
10.8 Handling Multiple Activities 315
10.8.1 Controlling Multiple Tasks 315
10.8.2 Controlling Multiple Threads 316
10.8.3 Thread Safety 318
10.9 Summary 321
Further Reading 321
Review Questions 322
Answers to Review Questions 323
11 Reusable Design Patterns 326
11.1 Introduction 328
11.1.1 A Brief History of Patterns 328
11.1.2 Software Patterns Today 329
11.2 A Pattern Template 330
11.3 Common Design Patterns 331
11.3.1 Observer 331
11.3.2 Singleton 337
11.3.3 Multiton 341
11.3.4 Iterator 342
11.3.5 Factory Method and Abstract Factory 346
11.3.6 State 347
11.3.7 Facade 352
11.3.8 Adapter 354
11.3.9 Strategy and Template Method 356
11.3.10 Flyweight 358
11.3.11 Composite 361
11.3.12 Proxy 364
11.4 Using Patterns 367
11.5 Discovering, Combining and Adapting Patterns 367
11.6 Summary 370
Further Reading 371
12 Specifying the Interfaces of Classes 372
12.1 Introduction 374
12.2 What Is a Specification? 375
12.3 Formal Specification 376
12.4 Informal Specification 378
12.5 Dynamic Checking 380
12.6 Object-Oriented Specification 382
12.6.1 Formal Specification in OCL 383
12.6.2 Informal Specification in Eiffel 384
12.7 Design by Contract 385
12.7.1 Contracts and Inheritance 389
12.7.2 Reducing Error-Checking Code 391
12.7.3 Enforcing the Contract 394
12.7.4 Application Firewalls 395
12.8 Informal Specification in Java 396
12.8.1 Documenting a Contract using Comments 396
12.8.2 Checking Conditions Dynamically 396
12.8.3 Signaling Contract Violations using RuntimeExceptions 397
12.8.4 External Systems 398
12.8.5 Enabling and Disabling Dynamic Checks 400
12.9 Summary 402
Further Reading 403
Review Questions 403
Answers to Review Questions 404
13 Continuous Testing 406
13.1 Introduction 408
13.2 Testing Terminology 408
13.2.1 Black-Box Testing 409
13.2.2 White-Box Testing 410
13.3 Types of Test 411
13.3.1 Unit Testing 412
13.3.2 Integration Testing 412
13.3.3 Alpha Testing 413
13.3.4 Beta Testing 413
13.3.5 Use Case Testing 414
13.3.6 Component Testing 414
13.3.7 Build Testing 415
13.3.8 Load Testing 417
13.3.9 Installation Testing 418
13.3.10 Acceptance Testing 418
13.3.11 Regression Tests 419
13.3.12 Documentation Tests 419
13.3.13 Testing for Security 419
13.3.14 Metrics 420
13.4 Automating Tests 421
13.5 Preparing for Testing 422
13.6 Testing Strategies 424
13.6.1 Testing During Development 424
13.6.2 Testing During the Testing Phase 425
13.6.3 Testing After Release 426
13.7 What to Test For 426
13.8 Test-Driven Development 430
13.9 An Example of Test-Driven Development using JUnit 431
13.9.1 Testing the Car Class 433
13.9.2 Implementing the Car Class 434
13.9.3 Refactoring Tests 435
13.9.4 Creating a Test Suite for Regression Testing 439
13.9.5 Testing Across Methods 441
13.9.6 Completing the Store Class 442
13.10 Summary 445
Further Reading 445
A Ripple Summary 446
B iCoot Case Study 450
B.1 Business Requirements 450
B.1.1 Customer’s Mission Statement 450
B.1.2 Actor List 450
B.1.3 Use Case List 451
B.1.4 Use Case Communication Diagrams 452
B.1.5 Use Case Activity Diagrams 452
B.1.6 Use Case Details 452
B.2 System Requirements 456
B.2.1 User Interface Sketches 456
B.2.2 Actor List 460
B.2.3 Use Case List 460
B.2.4 Use Case Diagram 460
B.2.5 Use Case Survey 461
B.2.6 Use Case Details 462
B.2.7 Supplementary Requirements 465
B.2.8 Use Case Priorities 465
B.3 Analysis 466
B.3.1 Class Diagram 466
B.3.2 Attributes 467
B.3.3 Operation List 467
B.3.4 State Machine for a Reservation 469
B.3.5 Use Case Realization 470
B.4 System Design 476
B.4.1 Technology Choices 476
B.4.2 Layer Diagram 477
B.4.3 Layer Interaction Policy 479
B.4.4 Packages 479
B.4.5 Deployment Diagram 479
B.4.6 Security Policy 482
B.4.7 Concurrency Policy 482
B.5 Subsystem Design 483
B.5.1 Business Services 483
B.5.2 ServletsLayer Class Diagram 483
B.5.3 ServletsLayer Field List 484
B.5.4 ServletsLayer Message List 484
B.5.5 ServerLayer Class Diagram 485
B.5.6 ServerLayer Field List 486
B.5.7 ServerLayer Message List 486
B.5.8 BusinessLayer Class Diagram 487
B.5.9 BusinessLayer Field List 488
B.5.10 Protocol Objects Class Diagram 492
B.5.11 Database Schema 494
B.5.12 User Interface Design 494
B.5.13 Business Service Realization 494
B.6 Class Specification 508
B.6.1 Server Class Specification 508
B.6.2 Business Logic Class Specification 509
B.7 Outline Test Plan 512
B.7.1 Introduction 512
B.7.2 The Impact of Spirals and Increments 512
B.7.3 Testing of Non-Code Artifacts 513
B.7.4 Code Reviews 513
B.7.5 Test-Driven Development 513
B.7.6 Assertions 514
B.7.7 Testing Phase 514
B.7.8 Documentation Testing 515
B.7.9 Build Testing 515
B.7.10 Test Documentation and Logging 515
B.7.11 Testing Activities by Phase 516
B.8 Glossary 517
C Summary of UML Notation Used 526
Bibliography 538
Index 541