Table Of ContentDeveloping Business Applications
with OpenStepTM
Springer Science+Business Media, LLC
Nik Gervae Peter Clark
Developing
Business Applications
with OpenStep™
With 37 Illustrations
~..,~, Springer
Library of Congress Cataloging-in-Publication Data
Gervae, Nik.
Developing business applications with OpenStep / Nik Gervae, Peter
Clark.
p. cm.
Inc1udes bibliographical references and index.
ISBN 978-0-387-94852-2 ISBN 978-1-4612-1852-4 (eBook)
DOI 10.1007/978-1-4612-1852-4
1. Application software-Development. 2. OpenStep 3. BusineS&
Data processing. 1. Clark, Peter. II. Title.
QA76.76.A65G46 1996
()()5.2~c20 96-32683
Printed on acid-free paper.
@ 1997 Springer Science+Business Media New York
Originally published by Springer-Verlag New York, Inc. 1997
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987654321
Contents
.
Foreword
• • • • • • • • • • • Xl
...
Preface..
• • • • • • • • • • XlU
..
Acknowledgments and Disclaimers .
•••• XVll
Part One: OpenStep
Chapter 1:WhatIs OpenStep? 3
The OpenStep Specification . . . . . . . . . . 4
Components ofthe OpenStep Specification . . . 6
User and Development Environments. . . . . . . . .12
NeXT's OPENSTEP Release 4 for Windows NT .12
SunSoft's OpenStep 1.0 for Solaris. . . . .13
NeXT's OPENSTEP Release 4 for Mach. . . . . .14
Chapter 2: The Object Model. . . . . . . . . . . . . . . . .15
Principles ofObject-Oriented Programming. .15
Encapsulation. .16
Inheritance . . .17
Polymorphism .18
Dynamism . . .18
Basics ofthe Objective-C Language. .20
Objects and Messages. . . . . . .21
Implementing Objects: Classes and Protocols .22
Run-Time Features. .27
Class Objects. . . . . . . . . . . . . . . . . .27
v
VI DevelopingBusinessApplicatiomwith OpenStep
The Root Class . .28
Object Lifetime. .28
Archiving.... .30
Objective-C and c++. .31
MixingObjective-C and C++. .33
Chapter3: The Foundation Framework. . . • • • • . • • • .35
The Classes. . . . . . . . . . . . .37
Core Run-Time Classes. . . . . . . . . . . . . . .37
Value and Collection Classes. . . . . . . . . . . .44,
Classes for Distributed Objects and Concurrency .48
Process Environment Classes. . . . . . . . . . . .50
Chapter4: TheApplication Kit. . • • . . . • • • . . • • • .53
Preliminaries . . . . . . . . . . .54
CoreApplication Functionality. .55
Graphical Structure. . . . . .56
Driving theApplication . . .60
Standard User Interface Controls. .64
Other FunctionalAreas. .65
Text and Fonts. .65
DrawingAids. . .67
Printing. . . . . .68
System Services. .69
Chapter 5: NeXT's OPENSTEP forWindows NT . • • . • .73
The UserInterface . . . . .74
User System Programs . . .7'5
Background Programs ./'5
DemoApplications. . .i'6
The Development Environment .76
Project Builder . .:7
Interface Builder .81
OtherTools . . .82
Chapter 6: SunSoft's Solaris OpenStep 85
The User Interface . . .85
User System Programs 88
Contents VII
Workspace Manager .88
Mail . .89
Edit . .89
Terminal . .90
Preview.. .91
Preferences . .91
The Development Environment .91
Project Builder . .92
Interface Builder .96
HeaderViewer . .96
Chapter7: BuildinganApplication 99
PayPerView: The Design . . 100
Creating the Project . . . . . . 101
Buildingthe Interface. . . . . . 103
Laying Out the Window . . 104
Creating the Controller Objects . 107
Connecting Interface Objects. . 109
Fleshing Out the Classes . . . . . . 110
The ProgramController Class. . 111
The Program Class . . . . . . 114
The OrderController Class. . 115
Buildingand Debugging . . 118
NeXT'sWay. .118
SunSoft'sWay. . . . . 120
Part Two: Business Applications
Chapter 8: The CharacterofaBusinessApplication .... 125
The Business Environment. . . . . . . · 125
Data, Process, and Policy. . . . . . · 126
The Elements ofaBusinessApplication · 127
Databases . · 127
Business Components . . . · 128
Business Entities . . . . . . .128
Presentation ofInformation .129
Elements as Objects . .129
DevelopingBusinessApplicationswith OpenStep
Vlll
Component Objects .129
Business Objects . . .130
Presentation Objects .130
AUnifiedApproach to BusinessApplications .131
Chapter9: DistributedApplications . . . . . . . . . . . . 13.3
What Distributed Objects Does . . . .133
PayPerViewwith Distributed Objects .134
HowItWorks . . . . . . .137
Advertising an Object. . . . .137
Contacting the Server. . . . .139
Remote Message Processing · 14:2
Transferring Dataand Objects. · 146
Handling Failures. . . . . . .148
Other Distribution Models. . . .149
Microsoft OLEAutomation .149
OMG's CORBA . · 15:2
Where Distributed Objects Falls Short . .153
Limitations in the Distribution Mechanism .154
Absent and Incomplete Services .154
MissingTook . . . . . . . . · 155
Design with Distributed Objects . .156
Performance . .157
Reliability. . . . .158
Concurrency . . · 159
Interoperability. · 160
Perspective . . . . . · 161
Chapter 10: DatabaseApplications 163
What the Enterprise Objects Framework Does. . 16Ll
What's an Enterprise Object? . . . . 165
Model-View-Controller Revisited . . 16<l
Specific Features . . . . . . . . . . . 16?
PayPerViewwith Enterprise Objects. . . 168
Defining the Relational-to-Object Mapping . . 16~)
Revising the User Interface and Code. . 174
Changes to ExistingCode . 180
How ItWorks . . . . . . . . . . . . . . . 181
Contents IX
TheAccess Layer . . .182
The Control Layer . .188
The Interface Layer. .194
Perspective . . . . . . . .196
Chapter 11:WorldWideWeb Applications 197
What WebObjects Does . . 199
The Pans ofa Page. . . . . . 199
Reusable Components . . . .200
Session State Management . .201
ASample Page Definition . . . . 202
How ItWorks. . . . . . . . . .204
The Request-Response Loop. .205
Following Hello World. .206
Perspective . . . . . . . . . . . . . 207
Part Three: Development Topics
Chapter 12: DevelopmentTopics . . . 211
Chapter 13: Project Management
and the Development Life Cycle. . . . . . . . . . . . . 213
Building Business Models. . .216
Constructing the Model . .216
Verifying the Model . . . .218
Choosing aMethodology. .219
Rapid Prototyping . . . . . .220
Iterative Development . . . .222
Schedulingand Milestones . .224
DefiningMilestones . .225
Revising the Schedule.. .227
The BenefitsofReuse.. .228
Chapter 14: Portability . . . . . . . . . . . . . . . . . . . 231
Guaranteed Portable . . . .232
Guaranteed Nonportable . .232
Gray Areas . . . . . . . . .233
x DevelopingBusinessApplicationswithOpenStep
System-Neutral Libraries and Tools .234
Additions to OpenStep . .234
Noncode Resources. . . . . . . . . .235
Chapter 15: Testingand Debugging .••••••.•••• 237
Debugging in OpenStep . . 238
Common ProblemAreas . . .23~)
Reference Counts. . . . .239
Run-Loop Asynchrony . .240
Noncode Logic: Nib Files and Models . .240
Exceptions . . . . . . 241
WeakTyping. . . . .242
Distributed Objects. . 243
Chapter 16: Performance •.••••.....••..••• 245
Measuring Performance .245
Improving Performance . . . . . . . . .246
TuningAlgorithms. . . . . . . . . . 247
Reducing Memoryand DiskUsage. .24~'
ManagingAutoreleased Objects . 248
Loading Resources on Demand. .248
Using C++ and Standard C. . . .249
UsingThreads and Distribution .249
Overriding Reference-Count Methods. .250
OverridingObjective-C Dynamism .250
Appendices
AppendixA: PayPerViewSource • •• 255
Appendix B: PayPerViewwith Distributed Objects. • • • •265
Appendix C: PayPerViewwith Enterprise Objects •• 271
Suggested Reading. · .. 281
Index . · •. 283
