Web 2.0 Projects

362 Pages·2007·5.2 MB·English

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EMPOWERING PRODUCTIVITY FOR THE JAVA™ DEVELOPER THE EXPERT’s VOICE® IN JAVA™ TECHNOLOGY
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Practical Apache Struts2 Web 2.0 Projects
Practical
Dear reader,
A
Apache Struts2 is the first major release of the most popular open source Java™ p
web application framework ever. This is an important milestone for the frame- a Practical Apache
work in terms of functionality but also for the improvements that have been c
made to increase developer productivity. By decreasing coupling within the h
framework, reducing configuration and proving default and different config- e
uration options (via annotations), and providing a plug-in mechanism to easily
Author of S Struts2
extend the base features, Struts2 is providing a platform that can be built upon
Starting Struts2 for the next generation of web applications.
t
My goal in writing this book is to introduce all the features of Struts2 to you
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in a practical and useful manner. I believe this approach benefits both new-
comers to web development (as you will learn all the necessary steps to build u
an application) and those transitioning from another technology (who will be
able to see the differences between application feature implementations). t
Developing a Web 2.0 application from start to finish will give you a deep s
understanding of Struts2: the core architectural elements, the interactions
2
between elements, and how each element is configured. Through a hands-on
Web 2.0 Projects
approach, you will learn about the features of Struts2 as a complete Web 2.0

application is developed from start to finish. You will learn about the basic features W
important to all web applications: data input, validation, data conversion,
e
internationalization, workflows/wizards, and security. Additionally, advanced
b
features that are the cornerstones of Web 2.0 applications—syndication, web

services, and AJAX user interfaces/integration—are explained in detail. 2
I hope you enjoy developing with the Struts2 framework as much as I do. .
0
Ian Roughley
P
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Learn and immediately apply the new agile open source
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THE APRESS JAVA™ ROADMAP Apache Struts2 web framework to your projects.
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Companion eBook The Definitive Guide
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Practical Apache Struts2
Beginning POJOs
Web 2.0 Projects

See last page for details
on $10 eBook version Practical JRuby on
Rails Web 2.0 Projects

R
o Ian Roughley
SOURCE CODE ONLINE ISBN-13: 978-1-59059-903-7 u
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h
53999 l Foreword by Patrick Lightbody,
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y
US $39.99 Struts2 co-creator
Shelve in
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User level:
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Intermediate–Advanced
this print for content only—size & color not accurate spine = 0.838" 360 page count

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Practical Apache
Struts2 Web 2.0
Projects
Ian Roughley
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Practical Apache Struts2 Web 2.0 Projects
Copyright © 2007 by Ian Roughley
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For Skooter.
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Contents at a Glance
Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
About the Author. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
About the Technical Reviewer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvi
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
nCHAPTER 1 Web 2.0 and Struts2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
nCHAPTER 2 Getting Up and Running. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
nCHAPTER 3 Framework Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
nCHAPTER 4 Application Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
nCHAPTER 5 Data Manipulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
nCHAPTER 6 Wizards and Workflows. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
nCHAPTER 7 Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
nCHAPTER 8 Searching and Listings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
nCHAPTER 9 Syndication and Integration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
nCHAPTER 10 AJAX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
nINDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
v
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Contents
Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
About the Author. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
About the Technical Reviewer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvi
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
nCHAPTER 1 Web 2.0 and Struts2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
What Is Web 2.0? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Web Application Development 2.0. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Web Framework Agility with Struts2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Using this Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
nCHAPTER 2 Getting Up and Running . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
The Build Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Maven2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
The Struts2 Starter Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
The Maven2-Generated Directory and File Structure . . . . . . . . . . . . 15
The Maven2 Configuration File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Starter Application Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
nCHAPTER 3 Framework Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Walking Through a Request-Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
The Request Initiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
The Struts2 Servlet Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
The Action Invocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
The Action. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Interceptors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
The Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
vii
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viii nCONTENTS
Exploring the Core Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Interceptors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Custom Interceptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
The Value Stack and OGNL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Results and Result Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Tag Libraries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Configuring the Elements of the Framework . . . . . . . . . . . . . . . . . . . . . . . . 52
The web.xml File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Zero Configuration Annotations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
The struts.xmlFile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Configuring the Execution Environment. . . . . . . . . . . . . . . . . . . . . . . . 65
Extending the Framework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
nCHAPTER 4 Application Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
The Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Use Cases. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Integration Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
The Domain Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
An Agile Development Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Continuous Integration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Integrating the Persistence Layer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Configuring the Dependencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Installing MySQL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Configuring Hibernate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Using Hibernate to Create Data Access Objects. . . . . . . . . . . . . . . . . 85
Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
nCHAPTER 5 Data Manipulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
The Use Case. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
CRUD Functionality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
The Domain Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Model-Driven Actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Setup Code and Data Prepopulation. . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96