Java

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THE

DESIGN PATTERNS
JAVA COMPANION

JAMES W. COOPER

October 2, 1998 Copyright © 1998, by James W. Cooper

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Some Background on Design Patterns
Defining Design Patterns This Book and its Parentage The Learning Process Studying Design Patterns Notes on Object Oriented Approaches The Java Foundation Classes Java Design Patterns

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1. CreationalPatterns

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The Factory Pattern
How a Factory Works Sample Code The Two Derived Classes Building the Factory Factory Patterns in Math Computation When to Use a Factory Pattern Thought Questions

The Abstract Factory Pattern
A GardenMaker Factory How the User Interface Works Consequences of Abstract Factory Thought Questions

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The SingletonPattern
Throwing the Exception Creating an Instance of the Class Static Classes as Singleton Patterns Creating Singleton Using a Static Method

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Finding the Singletons in a Large Program Other Consequences of the Singleton Pattern

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The Builder Pattern
An Investment Tracker Calling the Builders The List Box Builder The Checkbox Builder Consequences of the BuilderPattern Thought Questions

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The Prototype Pattern
Cloning in Java Using the Prototype Consequences of the Prototype Pattern

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Summary of Creational Patterns 2. The Java Foundation Classes
Ideas Behind Swing The Swing Class Hierarchy

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Installing and Using the JFC

Writing a Simple JFC Program
Setting the Look and Feel Settingthe Window Close Box Making a JxFrame Class A Simple Two Button Program More on JButtons

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Buttons and Toolbars
Radio Buttons The JToolBar Toggle Buttons

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Sample Code

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Menus and Actions
Action Objects Design Patterns in the Action Object

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The JList Class
List Selections and Events Changing a List Display Dynamically

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The JTable Class
A Simple JTable Program Cell Renderers

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The JTree Class
The TreeModel Interface Summary

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3. Structural Patterns

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The Adapter Pattern
Moving Data between Lists Using the JFC JList Class Two Way Adapters Pluggable Adapters Adapters in Java

The Bridge Pattern
Building a Bridge Consequences of the Bridge Pattern90
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The Composite Pattern
An Implementation of a Composite Building the Employee Tree Restrictions on Employee Classes

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Consequences of the Composite Pattern Other Implementation Issues

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The Decorator Pattern
Decorating a CoolButton Using a Decorator Inheritance Order Decorating Borders in Java Non-Visual Decorators Decorators, Adapters andComposites Consequences of the Decorator Pattern

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The Façade Pattern
Building the Façade Classes Consequences of the Façade

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The Flyweight Pattern
Discussion Example Code Flyweight Uses in Java Sharable Objects

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The Proxy Pattern
Sample Code Copy-on-Write Comparison with Related Patterns

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Summary ofstructural patterns 4. Behavioral Patterns
Applicability Sample Code

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Chain of Responsibility

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The List Boxes A Chain or a Tree? Kinds of Requests Examples in Java Consequences of the Chain of Responsibility

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The Command Pattern
Motivation The Command Pattern Building Command Objects The Command Pattern in Java Consequences of theCommand Pattern Providing Undo

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The Interpreter Pattern
Motivation Applicability Sample Code Interpreting the Language Objects Used in Parsing Reducing the Parsed Stack Consequences of the Interpreter Pattern

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The Iterator Pattern
Motivation Enumerations in Java Filtered Iterators Sample Code Consequence of the Iterator...