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359 Pages·2013·9.24 MB·English

by  Burt Beckwith

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www.it-ebooks.info
Programming Grails
Burt Beckwith
www.it-ebooks.info
Programming Grails
by Burt Beckwith
Copyright © 2013 Burt Beckwith. All rights reserved.
Printed in the United States of America.
Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472.
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May 2013: First Edition
Revision History for the First Edition:
2013-04-22: First release
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herein.
ISBN: 978-1-449-32393-6
[LSI]
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Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1. Introduction to Groovy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Installing Groovy 1
Groovy Console 2
Optional Typing 3
Collections and Maps 4
Properties 5
Using the AST Browser 7
Decompiling with JD-GUI 8
Decompiling with javap 8
Closures 8
Interface Coercion 11
Programmatic Closures 11
Owner, Delegate, and this 12
Groovy’s Contributions in the War Against Verbosity 13
Constructors 14
Checked Exceptions 15
Groovy Truth 15
Semicolons 16
Optional Return 16
Scope 16
Parentheses 16
Default Imports 16
Differences Between Java and Groovy 17
Array Initialization 17
in and def Keywords 17
do/while Loops 17
for Loops 17
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Annotations 18
Groovy Equality 18
Multimethod Dispatch 18
Groovy Strings 19
Static this 20
The Groovy JDK (GDK) 21
DefaultGroovyMethods and InvokerHelper 21
Metaprogramming and the MOP 21
Adding Methods 22
Intercepting Method Calls 23
Operators 26
Null-Safe Dereference 26
Elvis 26
Spread 27
Spaceship 27
Field Access 28
as 28
in 28
Method Reference 29
Overload Your Operators 29
Being Too Groovy 31
def Considered Harmful 31
Closures Versus Methods 32
TypeChecked, CompileStatic, and invokedynamic 33
2. Grails Internals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Installing Grails 38
Creating an Application 38
The Grails Command Line 39
IDE Support 41
Plugins 42
Optional Plugins 43
Core Plugins 45
Conventions 57
Controller and View Conventions 57
Service Conventions 60
Domain Class Conventions 61
More Information 65
3. Persistence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Data Mapping 67
Nonpersistent Domain Classes 69
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Data Validation 69
Custom Validation 72
Extreme Custom Validation 74
Validation Plugins 75
Friendly Error Messages 75
Blanks Versus Nulls 76
Transients 77
Mapping Collections 78
Querying 80
Saving, Updating, and Deleting 82
NoSQL Support 84
4. Spring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Inversion of Control and Dependency Injection 85
Complex Dependency Configuration Using Spring SpEL 86
Manually Injecting Dependencies at Runtime 87
Bean Scopes 87
Transactional Services 88
@Transactional 89
Transaction Proxies 90
Transaction Utility Methods 93
Bean Life Cycles and Interfaces 94
Bean Postprocessors 95
A Groovier Way 96
Bean Aliases 97
Internationalization 98
Resources 98
Resource Dependency Injection 99
ResourceLocator 100
Data Binding and Validation 101
Data Binding 101
Validation 102
Database Persistence 102
Thread-Local Holders 103
JdbcTemplate 103
Other Database Support 104
Spring MVC 104
Filters 105
Using Spring MVC Controllers 106
Remoting 107
Client Access 108
JMS 110
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EJBs 110
JMX 110
Email 111
Cache Abstraction 111
5. Hibernate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Mapping Domain Classes 113
Dialects 115
Dialect Autodetection 116
Dialect Customization 116
Hibernate Without GORM 118
hibernate.cfg.xml 118
HibernateUtil 119
Author 120
Book 120
Experimenting with the APIs 121
The Session 123
withSession 124
withNewSession 124
Open Session in View 124
Disabling OSIV 125
Custom User Types 126
Optimistic and Pessimistic Locking 129
Accessing the Session’s Connection 130
schema-export 130
SQL Logging 131
Proxies 133
equals, hashCode, and compareTo 134
Caching 135
Examples 136
Caching API 139
Query Caching Considered Harmful? 140
HQL 141
executeQuery 141
Query Syntax 142
Report Queries 143
Aggregate Functions 144
Expressions 145
Collections 145
Collections Performance 145
The Solution 146
Session.createFilter() 147
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Custom Configurations 148
Mapping Views and Subselect Classes 150
Subselect Domain Classes 152
Selecting with a POGO 153
get(), load(), and read() 154
get() 154
load() 154
read() 156
Performance 156
Caching 156
Lazy Loading 157
Transactional Write-Behind 158
6. Integration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
JMS 159
XA Support with the Atomikos Plugin 163
Mail 167
Sending Email 168
Sending Email Asynchronously 171
Sending Email from Log4j 172
Testing 174
SOAP Web Services 174
The Server Application 175
The Client Application 176
TCPMon 179
REST 180
TCPMon 187
JMX 188
7. Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
External config Files 191
Loading the Configuration 193
Partitioning Config Files 194
Splitting resources.groovy 195
Modularizing Within resources.groovy 196
Environment-Specific Spring Beans 198
Beans Closures in Config.groovy 201
Options for BuildConfig.groovy 201
Adding Additional Source Folders 202
Extra Folders Under grails-app 203
8. Plugins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
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Creating a Plugin 205
Initial Steps 206
The Plugin Descriptor 209
Metadata 209
Life Cycle Callbacks 213
Splitting Applications into Plugins 218
Inline Plugins 218
Building and Releasing 219
Automated Testing 219
Running the Tests 224
Custom Plugin Repositories 224
Plugin Documentation 226
Custom Artifacts 227
Some Notes on Plugin Development Workflow 232
9. Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
OWASP 235
A1: Injection 235
A2: Cross-Site Scripting (XSS) 238
A3: Broken Authentication and Session Management 241
A4: Insecure Direct Object References 242
A5: Cross-Site Request Forgery 244
A6: Security Misconfiguration 245
A7: Insecure Cryptographic Storage 246
A8: Failure to Restrict URL Access 248
A9: Insufficient Transport Layer Protection 248
A10: Unvalidated Redirects and Forwards 249
Security Plugins 250
spring-security-core 250
Other Plugins and Libraries 254
AntiSamy 254
ESAPI 254
HDIV 254
General Best Practices 255
10. The Cloud. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Cost Savings 262
What You Give Up 262
Cloud Foundry 263
Database Applications 263
Scaling 269
NoSQL, RabbitMQ, and Searchable 270
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