Pattern-oriented software architecture, vol.5: on patterns and pattern languages

491 Pages·2007·4.59 MB·English

by  Frank Buschmann

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P A T T E R N - O R I E N T E D
S O F T W A R E
A R C H I T E C T U R E
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PATTERN-ORIENTED
SOFTWARE
ARCHITECTURE
On Patterns and Pattern Languages
Volume 5
Frank Buschmann,
Siemens, Munich, Germany
Kevlin Henney,
Curbralan, Bristol, UK
Douglas C. Schmidt,
Vanderbilt University, Tennessee, USA
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†
For Anna, Bebé , and Martina
Frank Buschmann
For Carolyn, Stefan, and Yannick
Kevlin Henney
For Lori, Bronson, Mom, and Dad
Douglas C. Schmidt
For John
Frank Buschmann, Kevlin Henney, Douglas C. Schmidt
† Bebé, July 3, 1999
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Table of Contents
Foreword by Richard P. Gabriel . . . . . . . xiii
Foreword by Wayne Cool . . . . . . . . . . . . . xxiii
About the Authors . . . . . . . . . . . . . . . . . . . xxix
About this Book . . . . . . . . . . . . . . . . . . . . . xxxi
Guide to the Reader . . . . . . . . . . . . . . . . . . xxxvii
0 Beyond the Hype . . . . . . . . . . . . . . . . . . . . . . . 1
0.1 Beginnings… . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
0.2 A Story of Success… with Some Exceptions . . . . 3
0.3 Pattern Definitions and their Interpretations . . . 8
0.4 Toward a Deeper Understanding of Patterns . . . . 19
Part I Inside Patterns . . . . . . . . . . . . . . . . . . . . . . . . 25
1 A Solution to a Problem and More . . . . . . . . . . 29
1.1 A Solution to a Problem . . . . . . . . . . . . . . . . . . . 30
1.2 A Process and a Thing . . . . . . . . . . . . . . . . . . . . 32
1.3 Best of Breed . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
1.4 Forces: the Heart of Every Pattern . . . . . . . . . . . 36
1.5 The Context: Part of a Pattern or Not? . . . . . . . . 42
1.6 Genericity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
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viii Contents
1.7 A Diagram Says More than a Thousand Words…
or Less . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
1.8 Evocative Names Help Pattern Recollection . . . . 54
1.9 Patterns are Works in Progress . . . . . . . . . . . . . 57
1.10 A Pattern Tells a Story and Initiates a Dialog . . . 61
1.11 A Pattern Celebrates Human Intelligence . . . . . . 62
1.12 From a Problem–Solution Statement to a
Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
2 A Million Different Implementations . . . . . . . 65
2.1 Does One Size Fit All? . . . . . . . . . . . . . . . . . . . . 66
2.2 Patterns and Frameworks . . . . . . . . . . . . . . . . . 77
2.3 Patterns and Formalisms . . . . . . . . . . . . . . . . . 84
2.4 A Million and One… and then Some . . . . . . . . . 87
3 Notes on Pattern Form . . . . . . . . . . . . . . . . . . 91
3.1 Style and Substance . . . . . . . . . . . . . . . . . . . . . 92
3.2 The Function of Form . . . . . . . . . . . . . . . . . . . . 96
3.3 Elements of Form . . . . . . . . . . . . . . . . . . . . . . . 97
3.4 Details, Details . . . . . . . . . . . . . . . . . . . . . . . . . 102
3.5 Aerial View . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
3.6 Different Pattern Forms . . . . . . . . . . . . . . . . . . . 110
3.7 Style and Substance (Redux) . . . . . . . . . . . . . . . 116
Part II Between Patterns . . . . . . . . . . . . . . . . . . . . . . 117
4 Pattern Islands? . . . . . . . . . . . . . . . . . . . . . . . 121
4.1 Patterns Connect . . . . . . . . . . . . . . . . . . . . . . . 122
4.2 A Design Experiment: Patterns as Islands . . . . . 123
4.3 A Second Design Experiment: Interwoven
Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
4.4 Pattern Density . . . . . . . . . . . . . . . . . . . . . . . . . 131
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Contents ix
5 Pattern Complements . . . . . . . . . . . . . . . . . . . 135
5.1 More than One Solution to a Problem . . . . . . . . . 136
5.2 Patterns in Competition . . . . . . . . . . . . . . . . . . . 138
5.3 Patterns in Cooperation . . . . . . . . . . . . . . . . . . . 155
5.4 Patterns in Combination . . . . . . . . . . . . . . . . . . 159
5.5 Complementary: Competing, Completing,
Combining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
6 Pattern Compounds . . . . . . . . . . . . . . . . . . . . . 165
6.1 Recurring Pattern Arrangements . . . . . . . . . . . . 166
6.2 From Elements to Compounds . . . . . . . . . . . . . . 166
6.3 From Complements to Compounds . . . . . . . . . . 173
6.4 Element or Compound? . . . . . . . . . . . . . . . . . . . 176
6.5 Compound Analysis and Synthesis . . . . . . . . . . 180
7 Pattern Sequences . . . . . . . . . . . . . . . . . . . . . . 183
7.1 Patterns Tell Software Engineering Success
Stories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
7.2 Pattern Stories . . . . . . . . . . . . . . . . . . . . . . . . . . 185
7.3 From Stories to Sequences . . . . . . . . . . . . . . . . . 191
7.4 Sequences of Patterns . . . . . . . . . . . . . . . . . . . . 192
7.5 Pattern Compounds and Complements
Revisited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
7.6 Returning to the Question of Context . . . . . . . . . 203
7.7 Pattern Connections . . . . . . . . . . . . . . . . . . . . . . 207
8 Pattern Collections . . . . . . . . . . . . . . . . . . . . . 209
8.1 Toward a Handbook . . . . . . . . . . . . . . . . . . . . . . 210
8.2 Organizing Pattern Collections . . . . . . . . . . . . . . 211
8.3 Ad Hoc Organization . . . . . . . . . . . . . . . . . . . . . 212
8.4 Organization by Level . . . . . . . . . . . . . . . . . . . . . 213
8.5 Organization by Domain . . . . . . . . . . . . . . . . . . 218
8.6 Organization by Partition . . . . . . . . . . . . . . . . . . 219
8.7 Organization by Intent . . . . . . . . . . . . . . . . . . . . 221