Beginning Hibernate

391 Pages·2010·8.377 MB·English

by  Jeff Linwood, Dave Minter (auth.)

Beginning Hibernate
Second Edition

■ ■ ■
Jeff Linwood and Dave Minter
Beginning Hibernate, Second Edition
Copyright © 2010 by Jeff Linwood and Dave Minter
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ISBN-13 (pbk): 978-1-4302-2850-9
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Contents at a Glance
About the Authors ..................................................................................................... xv

About the Technical Reviewer ................................................................................. xvi
Acknowledgments .................................................................................................. xvii
Introduction ........................................................................................................... xviii

■Chapter 1: An Introduction to Hibernate 3.5 ............................................................ 1
■Chapter 2: Integrating and Configuring Hibernate................................................... 9
■Chapter 3: Building a Simple Application .............................................................. 27
■Chapter 4: The Persistence Life Cycle ................................................................... 61
■Chapter 5: An Overview of Mapping ...................................................................... 77
■Chapter 6: Mapping with Annotations ................................................................... 91
■Chapter 7: Creating Mappings with Hibernate XML Files ................................... 133
■Chapter 8: Using the Session ............................................................................... 177
■Chapter 9: Searches and Queries ........................................................................ 193
■Chapter 10: Advanced Queries Using Criteria...................................................... 215
■Chapter 11: Filtering the Results of Searches ..................................................... 227
■Chapter 12: Case Study – Using Hibernate with an Existing Database ................ 235

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■ CONTENTS AT A GLANCE
■Appendix A: More Advanced Features ................................................................. 263
■Appendix B: Hibernate Tools................................................................................ 287
■Appendix C: Hibernate and Spring ....................................................................... 327
■Appendix D: Upgrading from Hibernate 2 ............................................................ 337

Index ....................................................................................................................... 343
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Contents
About the Authors ..................................................................................................... xv

About the Technical Reviewer ................................................................................. xvi
Acknowledgments .................................................................................................. xvii
Introduction ........................................................................................................... xviii

■Chapter 1: An Introduction to Hibernate 3.5 ............................................................ 1
Plain Old Java Objects (POJOs) .......................................................................................... 1
Origins of Hibernate and Object-Relational Mapping ........................................................ 3
Hibernate As a Persistence Solution .................................................................................. 4
A Hibernate Hello World Example ...................................................................................... 5
Mappings ........................................................................................................................... 6
Summary ........................................................................................................................... 7
■Chapter 2: Integrating and Configuring Hibernate................................................... 9
The Steps Needed to Integrate and Configure Hibernate .................................................. 9
Understanding Where Hibernate Fits in Your Java Application ....................................... 10
Deploying Hibernate ........................................................................................................ 11
Required Libraries for Running Hibernate 3.5 ........................................................................................ 11
JMX and Hibernate ................................................................................................................................. 12

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■ CONTENTS
Hibernate Configuration ................................................................................................... 12
Hibernate Properties ............................................................................................................................... 14
XML Configuration .................................................................................................................................. 18
Annotated Classes .................................................................................................................................. 19
Naming Strategy ..................................................................................................................................... 20
Using a Container-Managed Data Source............................................................................................... 21
The Session Factory ........................................................................................................ 21
SQL Dialects ..................................................................................................................... 22
Summary ......................................................................................................................... 25
■Chapter 3: Building a Simple Application .............................................................. 27
Installing the Tools ........................................................................................................... 27
Hibernate and Hibernate Tools ............................................................................................................... 27
Simple Logging Facade for Java (SLF4J) 1.5.11 .................................................................................... 28
HSQLDB 2.0.0 ......................................................................................................................................... 28
Ant 1.8.0 ................................................................................................................................................. 29
The Ant Tasks ......................................................................................................................................... 32
Creating a Hibernate Configuration File ........................................................................... 33
Running the Message Example ....................................................................................... 35
Persisting Multiple Objects .............................................................................................. 38
Creating Persistence Classes .......................................................................................... 39
Creating the Object Mappings ......................................................................................... 42
Creating the Tables .......................................................................................................... 48
Sessions .......................................................................................................................... 50
The Session and Related Objects ........................................................................................................... 50
Using the Session ................................................................................................................................... 52
The Example Client .......................................................................................................... 54
Summary ......................................................................................................................... 59
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■ CONTENTS
■Chapter 4: The Persistence Life Cycle ................................................................... 61
Introduction to the Life Cycle ........................................................................................... 61
Entities, Classes, and Names .......................................................................................... 62
Identifiers ......................................................................................................................... 63
Entities and Associations ................................................................................................. 63
Saving Entities ................................................................................................................. 67
Object Equality and Identity ............................................................................................. 68
Loading Entities ............................................................................................................... 69
Refreshing Entities........................................................................................................... 70
Updating Entities .............................................................................................................. 71
Deleting Entities ............................................................................................................... 72
Cascading Operations ...................................................................................................... 72
Lazy Loading, Proxies, and Collection Wrappers ............................................................. 74
Querying Objects ............................................................................................................. 75
Summary ......................................................................................................................... 75
■Chapter 5: An Overview of Mapping ...................................................................... 77
Why Mapping Cannot Be Automated ............................................................................... 78
Primary Keys .................................................................................................................... 80
Lazy Loading .................................................................................................................... 82
Associations ..................................................................................................................... 82
The One-to-One Association ................................................................................................................... 84
The One-to-Many and Many-to-One Association ................................................................................... 86
The Many-to-Many Association .............................................................................................................. 88
Applying Mappings to Associations ........................................................................................................ 89

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■ CONTENTS
Other Information Represented in Mappings ................................................................... 89
Specification of (Database) Column Types and Sizes ............................................................................. 89
The Mapping of Inheritance Relationships to the Database ................................................................... 89
Primary Key ............................................................................................................................................ 90
The Use of SQL Formula–Based Properties ............................................................................................ 90
Mandatory and Unique Constraints ........................................................................................................ 90
Cascading of Operations ......................................................................................................................... 90
Summary ......................................................................................................................... 90
■Chapter 6: Mapping with Annotations ................................................................... 91
Creating Hibernate Mappings with Annotations .............................................................. 91
Cons of Annotations ................................................................................................................................ 91
Pros of Annotations ................................................................................................................................ 91
Choosing Which to Use ........................................................................................................................... 93
Using Annotations in Your Application .................................................................................................... 93
JPA 2 Persistence Annotations ............................................................................................................... 93
Entity Beans with @Entity ...................................................................................................................... 95
Primary Keys with @Id and @GeneratedValue ....................................................................................... 95
Generating Primary Key Values with @SequenceGenerator .................................................................. 97
Generating Primary Key Values with @TableGenerator.......................................................................... 98
Compound Primary Keys with @Id, @IdClass, or @EmbeddedId ........................................................... 99
Database Table Mapping with @Table and @SecondaryTable ............................................................ 103
Persisting Basic Types with @Basic..................................................................................................... 105
Omitting Persistence with @Transient ................................................................................................. 105
Mapping Properties and Fields with @Column .................................................................................... 106
Modeling Entity Relationships .............................................................................................................. 107
Inheritance ............................................................................................................................................ 114
Other JPA 2 Persistence Annotations ................................................................................................... 117
Ordering Collections with @OrderColumn ............................................................................................ 119
Configuring the Annotated Classes ................................................................................ 121
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■ CONTENTS
Hibernate 3–Specific Persistence Annotations .............................................................. 122
@Entity ................................................................................................................................................. 123
Sorting Collections with @Sort ............................................................................................................. 123
Applying Indexes with @Table and @Index ......................................................................................... 124
Restricting Collections with @Where ................................................................................................... 124
Alternative Key Generation Strategies with @GenericGenerator .......................................................... 124
Using Ant with Annotation-Based Mappings ................................................................. 125
Code Listings ................................................................................................................. 126
Summary ....................................................................................................................... 131
■Chapter 7: Creating Mappings with Hibernate XML Files ................................... 133
Hibernate Types ............................................................................................................. 133
Entities .................................................................................................................................................. 133
Components .......................................................................................................................................... 134
Values ................................................................................................................................................... 134
The Anatomy of a Mapping File ..................................................................................... 136
The <hibernate-mapping> Element ..................................................................................................... 136
The <class> Element ........................................................................................................................... 138
The <id> Element ................................................................................................................................. 141
The <property> Element ...................................................................................................................... 144
The <component> Element .................................................................................................................. 146
The <one-to-one> Element .................................................................................................................. 147
The <many-to-one> Element ............................................................................................................... 149
The Collection Elements ....................................................................................................................... 152
Mapping Simple Classes................................................................................................ 160
Mapping Composition .................................................................................................... 162
Mapping Other Associations .......................................................................................... 165
Mapping Collections ...................................................................................................... 168

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