Struts

Struts 2 in Action

Struts 2 in Action
DONALD BROWN CHAD MICHAEL DAVIS SCOTT STANLICK

MANNING
Greenwich (74° w. long.)

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Copyeditor: Benjamin Berg Typesetter: Gordan Salinovic Cover designer: Leslie Haimes

ISBN1-933988-07-X Printed in the United States of America 1 2 3 4 5 6 7 8 9 10 – MAL – 13 12 11 10 09 08

To world peace and a global redistribution of prosperity

brief contents
PART 1 STRUTS 2: A BRAND NEW FRAMEWORK ..................................1
1 2
■ ■

Struts 2: the modern web application framework Saying hello to Struts 2 20

3

PART 2

CORE CONCEPTS: ACTIONS, INTERCEPTORS, ANDTYPE CONVERSION ...................................................41
3 4 5
■ ■ ■

Working with Struts 2 actions

43 74 101

Adding workflow with interceptors

Data transfer: OGNL and type conversion

PART 3

BUILDING THE VIEW: TAGS AND RESULTS ...........................129
6 7 8
■ ■ ■

Building a view: tags UI component tags Results in detail 202

131 167

vii

PART 4IMPROVING YOUR APPLICATION .......................................229
9 10 11
■ ■ ■

Integrating with Spring and Hibernate/JPA Exploring the validation framework Understanding internationalization 255 282

231

PART 5

ADVANCED TOPICS AND BEST PRACTICES ............................307
12 13 14 15
■ ■ ■ ■

Extending Struts 2 with plug-ins Best practices 326 360

309

Migration fromStruts Classic 339 Advanced topics

contents
preface xvii acknowledgments xix about this book xxii about the title xxvii about the cover illustration xxviii

PART 1 STRUTS 2: A BRAND NEW FRAMEWORK ......................1

1

Struts 2: the modern web application framework 3
1.1 Web applications: a quick study
■

4
■

Using the Web to build applications 4 Examining the technologystack 4 Surveying the domain 8

1.2 1.3

Frameworks for web applications
What’s a framework? 10
■

9
10

Why use a framework?

The Struts 2 framework 11
A brief history 11 Struts 2 from 30,000 feet: the MVC pattern 12 How Struts 2 works 15
■ ■

1.4

Summary

18

ix

x

CONTENTS

2

Saying hello to Struts 2 20
2.1 Declarative architecture 21
Two kinds ofconfiguration 21 Two mechanisms for declaring your architecture 22 Intelligent defaults 25
■ ■

2.2

A quick hello

25
■

Deploying the sample application 26 application 30

Exploring the HelloWorld

2.3 2.4

HelloWorld using annotations Summary 38

36

PART 2 CORE CONCEPTS: ACTIONS, INTERCEPTORS, AND TYPE CONVERSION .......................................41

3

Working with Struts...