Object-Oriented Programming in ColdFusion

Matt Gifford

• Publisher: Packt Publishing
• Year: 2010
• eBook ISBN: 9781847196323
• Edition: 1
• Topic: Computer Science
• Subtopic: Programming
• Index: Computer Science

In Detail

Are you tired of procedural programming or is your extensive code base starting to become un-manageable? Breathe some new life into your code and improve your development skills with the basic concepts of object-oriented programming. Utilize objects, modular components, and design patterns to expand your skills and improve your ColdFusion applications. Packed with example code, and written in a friendly, easy-to-read style, this book is just what you need if you are serious about ColdFusion.

This book is a fast-paced tutorial to important ColdFusion object-oriented programming topics. It will give you clear, concise, and practical guidance to take you from the basics of ColdFusion to the skills that will make you a ColdFusion developer to be reckoned with. Don't be put off by jargon or complex diagrams; read and see how you can benefit from this book and extend your development skills in the process.

Using the practical examples within this guide, you will learn how to structure your applications and code, applying the fundamental basics of object-oriented programming to develop modular, reusable components that will scale easily with your application. You will learn the basic fundamental practices of object-oriented programming, from object creation and re-use, to Bean objects, service layers, Data Access objects, and sample design patterns to gain a better understanding of OOP using examples that can be altered and applied in your application. Complete with detailed code samples and snippets, and written in a friendly easy-to-follow style, you will be able to break free from writing purely procedural code and enhance your applications by building structured applications utilizing basic design patterns and object-oriented principles.

An introduction to object-oriented programming in ColdFusion

Approach

This book is a fast-paced tutorial to developing ColdFusion applications using an object-oriented programming approach. Complete with code examples that can be altered and applied to your application and careful explanations, this book will guide you through your first interaction with object-oriented programming within your ColdFusion applications.

Who this book is for

If you are a web developer wanting to implement object-oriented programming with ColdFusion, then this book is for you. If your goal is to get a good grounding in the basics of object-oriented programming concepts, this book is perfect for you. No prior knowledge of object-oriented programming is expected, but basic knowledge of ColdFusion development skills is assumed.

Object-Oriented Programming in ColdFusion

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Table of Contents

Object-Oriented Programming in ColdFusion

Credits

Foreword

About the Author

Acknowledgement

About the Reviewer

Preface

Who this book is for

What this book covers

What you need for this book

Conventions

Reader feedback

Customer support

Errata

Piracy

Questions

1. Introducing ColdFusion Components

Why use CFCs?

Grouping your functions

Organizing your components

The ColdFusion component tags

Our first component

Defining a method

Returning the data

ColdFusion 9 scripted components

Creating your object

Restricting your functions to scopes

Using arguments within your methods

The Arguments scope

Redefine the function parameters

Combining your methods

Protecting your local variables

Using the Var scope

Placing your Var scoped variables

Naming your Var scoped variables

Accessing your CFC

Instantiating the object

Using the createObject function

Using the cfobject tag

Using the NEW operator

Using cfinvoke

The cfinvoke tag

Using cfinvokeargument

Using attributes as arguments

Using an argument collection

Passing arguments into an instance method call

As a list

As named values

As an argumentCollection

Arguments in action

Merging your functions into one

Using cfargument to combine your methods

Creating an object constructor

Creating an init() function

The Variables scope

Calling your init() function

The This scope

Summary

2. Effective Component Development

Pseudo-constructors

Using the pseudo method

Suppressing whitespace

Output attribute

Pseudo-constructor or init() method

Returning values and variables

returnType

Access properties

Private

Package

Public

Remote

Getting information about your CFC

Introspection

CFC Explorer

Component Doc

Document your code

Benefits of documentation

Displayname attribute

Hint attribute

Description attribute

User-defined metadata

Obtaining CFC metadata

getMetaData

getComponentMetaData

Returning metadata

Detailed introspection

Summary

3. Building Your First Bean

What is a Bean?

But what is it really?

The benefit of using beans

Creating our first Bean

An introduction to UML

Person object in UML

What makes a Bean a Bean

A default/no-argument constructor

Easily accessible for introspection

Setters/Mutators

Getters/Accessors

Completing our Projects Bean

Calling our project Bean

Populating the Bean

Read/Write Bean

Read-only Bean

Helpful objects

Implicit accessors

Summary

4. Inheritance and Object-Oriented Concepts

What is Inheritance?

Avoiding code duplication

Inheriting our products

The Super keyword

Overriding methods

Instantiating our products

The inheritance hierarchy

Specialization

The "IS A" relationship

Polymorphism

Composition

The "HAS A" Relationship

Implied ownership

Aggregation

Summary

5. Data Access Objects

What is a Data Access Object?

Creating a Data Access Object

The create method

Storing a new user

The read method

Handling select results

The update method

The delete method

An alternative save method

The save method

The exists method

Caching the Data Access Objects

Dependency Injection

Summary

6. Gateways

What is a Gateway?

A typical ColdFusion Gateway

Creating a Gateway object

Naming conventions

Adding gateway methods

Minimising code duplication

Revising the gateway object

Caching the Gateway object

The Gateway discussion

No hard and fast rules

Table Data Gateway

Similarities to Data Access Objects

Combining the two patterns

Which option is best?

Summary

7. Creating a Service Layer

What is a Service Layer?

Facade patterns in a nutshell

Creating a service

Defining the User Service

Adding the CRUD methods

Adding the Gateway methods

Adding an abstract class

Defining the address service

onApplicationStart (revisited)

Summary

Index

Object-Oriented Programming in ColdFusion

Copyright © 2009 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: October 2010

Production Reference: 1081010

Published by Packt Publishing Ltd. 32 Lincoln Road Olton Birmingham, B27 6PA, UK.

ISBN 978-1-847196-32-3

www.packtpub.com

Cover Image by Filippo ( <[email protected]> )

Credits

Author

Matt Gifford

Reviewer

Raymond Camden

Acquisition Editor

David Barnes

Development Editor

Dhiraj Chandiramani

Rakesh Shejwal

Technical Editor

Arun Nadar

Copy Editor

Laxmi Subramanian

Indexer

Rekha Nair

Editorial Team Leader

Aditya Belpathak

Project Team Leader

Priya Mukherji

Project Coordinator

Leena Purkait

Proofreader

Lynda Sliwoski

Production Coordinator

Alwin Roy

Cover Work

Alwin Roy

Foreword

ColdFusion Components (or CFCs) were introduced in ColdFusion MX back in 2002, and since then they have become one of the most important and fundamental building blocks for ColdFusion developers. In fact, recent releases of ColdFusion have made CFC use mandatory, by introducing features that are only available through ColdFusion Components.

As you'd expect from ColdFusion, CFCs are easy to learn and even easier to use. But the beautiful simplicity of ColdFusion Components hides a powerful, sophisticated, and proven Java-based framework on which developers can build highly scalable and manageable applications. Like all ColdFusion features, CFCs can be as simple or as sophisticated as your application requires, and developers can start reaping their benefits easily and painlessly, adding functionality and complexity later as needed.

But this duel personality, highly accessible simplicity on the one hand and all that power on the other, has proven to be a bit of a double-edged sword. The same ease of use that makes ColdFusion so easy to learn and so productive, also makes it too easy to never fully explore and leverage all that ColdFusion has to offer.

This is why I am so glad to see Matt Gifford's hard work take the form of this book. Matt starts with the basics of ColdFusion Components, but then quickly delves into the subtleties and complexities of using them for object-oriented development, demonstrating both the how's and why's, as well as the tips and tricks needed to truly appreciate how ColdFusion Components can (and should) change the way you build your next ColdFusion application.

Matt, this book is long overdue, and your contribution to the ColdFusion community is greatly appreciated. Thanks!

Ben Forta

Director of Platform Evangelism

Adobe Systems

When you start using ColdFusion components, you know that you're on the right track; you can feel this change at some core, instinctual level as if you're about to embrace something that holds tremendous, yet untapped potential. Unfortunately, your instincts won't take you much further beyond this point. The cold reality is, Object-Oriented Programming (OOP), ...

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• Object-Oriented Programming in ColdFusion