Introduction

• Whats our World?
• OK  So Just What is a Design Pattern?
• Design Patterns are not Esoteric
• Why Use Patterns?
• The Adapter Pattern
• Reviewing Interfaces & Abstract Classes
• Interface Types
• Interface Definitions
• Abstract Methods
• Abstract Classes
• Using Abstract Classes
• Important Principal of OO Design

The Iterator Pattern

• Patterns: Traversing a Collection
• A Simple ArrayList
• Using Our ArrayList
• Using Our Simple Collection
• Another Design for Collection Traversal
• Using Our New Collection
• Differences in Traversing Our Collection
• Why is This Important?
• Why is This a Design Pattern?
• We Will Expand on Our Design

Design Patterns  Background

• Design Patterns Arise From Architecture
• Christopher Alexander
• The TimelessWay
• A Core Principle of His Books
• Patterns in A Pattern Language
• Sitting Circle (185)
• Different Chairs (251)
• Patterns Evolution in Software
• OOPSLA 88
• Patterns Evolution in Software
• Patterns Today

UML Overview

• Unified Modeling Language (UML)
• Using UML
• UML Diagrams
• Class Diagram
• Class Diagram Notation
• Association Relationships in Detail
• Class Diagram Notation
• Abstract Class Notation
• Interface Notation
• Another Class Diagram

Gang of Four Design Patterns Description

• What Do We Know Now About Patterns
• GOF Pattern Description
• Iterator: Overview
• Iterator: Motivation
• Iterator: Applicability
• Iterator: Structure  Java
• Iterator: Structure  General
• Iterator: Participants
• Iterator: Collaborations and Consequences
• Iterator: Implementation
• Implementation: Who Controls the Iteration
• Implementation: Who Defines the Traversal
• Implementation: Robustness
• Iterator: Known Uses and Related Patterns
• So  What is a Design Pattern?

The GOF Patterns Catalog

• Organizing the Catalog
• Creational, Structural, and Behavioral Purpose
• Class and Object Scope
• Design Pattern Space
• The GOF Catalog of Design Patterns

Factory Method Pattern

• Motivation  Forces and Solution
• Motivation
• Factor Method: Iterator Usage
• Factory Method: General Structure
• Participants
• Collaborations and Applicability
• Applicability
• Consequences
• Implementation
• Known Uses and Related Patterns

Strategy Pattern

• Motivation  Forces and Solution
• Structure
• Alternative to Strategy
• How Do We Choose Among Alternative?
• Participants
• Collaborations and Applicability
• Consequences
• Implementation
• Known Uses and Related Patterns
• Difference From Factory Method

Decorator Pattern

• Motivation  Forces and Solution
• Structure
• Participants an Collaborations
• Structure
• Writer and FilterWriter Classes
• UpperCaseFilterWriter Class
• Consequences
• Implementation
• Known Uses and Related patterns

Composite Pattern

• Motivation  Forces
• Motivation  Solution
• Structure
• Participants
• Collaborations
• Consequences
• Implementation
• Known Uses and Related Patterns

Template Method Pattern

• Motivation  Forces and Solution
• Structure
• Participants and Collaborations
• Consequences
• Implementation
• Known Uses and Related Patterns

Command Pattern

• Motivation  Forces and Solution
• Structure
• Participants and Collaborations
• Consequences
• Implementation
• Undo and Redo
• Known Uses

Chain of Responsibility Pattern

• Motivation  Forces
• Motivation  Solution
• Structure
• Participants and Collaborations
• Consequences/Applicability
• Implementation
• Known Uses and Related Patterns

Faade Pattern

• Motivation  Forces and Solution
• Structure
• Participants and Collaborations
• Consequences/Applicability
• Implementation
• Known Uses

Patterns for Enterprise Systems

• Meeting the Challenge  Technologies
• Meeting the Challenge  Best Practices
• Some Patterns for Enterprise Systems
• Business Delegate
• Business Delegate: Solution
• Business Delegate: Structure
• Business Delegate: Consequences
• Value Object
• Value Object: Solution
• Value Object: Structure
• Value Object: Consequences
• Data Access Object (DAO)
• DAO: Solution
• DAO: Structure
• DAO: Consequences
• Lazy Load
• Lazy Load: Solution
• Lazy Load: Consequences

Wrap-Up

• What Have We Done?
• So  What Do You Think About Patterns?
• Where Do We Go From Here?
• Do We Fit Into Alexanders Vision?
• Design Patterns Isnt All You Need
• Have Fun