The Definitive Guide
to Grails
Second Edition
■■■
Graeme Rocher and Jeff Brown
The Definitive Guide to Grails, Second Edition
Copyright © 2009 by Graeme Rocher, Jeff Brown
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To Birjinia, the love and support you have given me in the last few years will stay with me
forever. Unquestionably yours. Maite zaitut.
—Graeme Rocher
To Betsy, Jake, and Zack, the best team ever.
—Jeff Brown
v
Contents at a Glance
About the Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
About the Technical Reviewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxv
■CHAPTER 1 The Essence of Grails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
■CHAPTER 2 Getting Started with Grails. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
■CHAPTER 3 Understanding Domain Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
■CHAPTER 4 Understanding Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
■CHAPTER 5 Understanding Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
■CHAPTER 6 Mapping URLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
■CHAPTER 7 Internationalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
■CHAPTER 8 Ajax. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
■CHAPTER 9 Creating Web Flows. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
■CHAPTER 10 GORM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
■CHAPTER 11 Services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
■CHAPTER 12 Integrating Grails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
■CHAPTER 13 Plugins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
■CHAPTER 14 Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
■CHAPTER 15 Web Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449
■CHAPTER 16 Leveraging Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 487
■CHAPTER 17 Legacy Integration with Hibernate . . . . . . . . . . . . . . . . . . . . . . . . . . . 519
■APPENDIX The Groovy Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545
■INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
