Just Hibernate

139 Pages·2014·5.57 MB·English

by  Madhusudhan Konda

Just Hibernate
Madhusudhan Konda
Just Hibernate
by Madhusudhan Konda
Copyright © 2014 Madhusudhan Konda. All rights reserved.
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June 2014: First Edition
Revision History for the First Edition:
2014-06-04: First release
2014-06-27: Second release
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ISBN: 978-1-449-33437-6
[LSI]
In memory of my loving Dad; we all miss you!

Table of Contents
Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1. Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Birth of Hibernate 1
Problem Domain 3
MovieManager Application 3
Improvising the Movie Application 6
Using Hibernate 8
Configure the Database Connection 9
Create Mapping Definitions 10
Persist the Objects 11
Creating the Persist Method 12
Testing the Persisted Data 13
Setting Up Hibernate 14
Summary 15
2. Fundamentals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Object-Relational Mismatch 17
Inheritance Mismatch 18
Identity Mismatch 18
Relations and Associations Mismatch 19
Hibernate’s Main Parts 19
Persistent Classes 20
Example: Trading Application 20
Using Annotations 20
Configuration 22
Using a Properties File 22
Using the XML File 23
v
Configuration Properties 23
Programmatic Configuration 23
Mapping 24
XML Mapping Files 24
Identifier Generation Strategies 26
Session APIs 27
Transactions 28
Summary 30
3. Annotations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Working Through an Example 31
Digging into Details 33
ID Generation Strategies 34
Composite Identifiers 36
Using Primary Key Class and @Id 36
Using Primary Key Class and @EmbeddedId 37
Using @IdClass 38
Summary 39
4. Persisting Collections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Designing to Interfaces 41
Persisting Lists 42
List Example: Car Showroom 42
Test Client for List Persistence 44
Persisting Sets 45
Persisting Maps 47
Persisting Arrays 49
Persisting Bags and IdBags 50
Persisting Collections Using Annotations 52
Using a Foreign Key 52
Using a Join Table 54
Summary 55
5. Associations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Associations 57
Multiplicity 58
Directionality 59
One-to-One Association 60
Using a Primary Key 61
Testing the Association 63
Using a Foreign Key 64
Annotations 66
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One-to-Many (or Many-to-One) Association 67
Bidirectional One-to-Many Association 70
Many-to-Many Association 71
Summary 72
6. Advanced Concepts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Hibernate Types 73
Entity and Value Types 73
Custom Types 74
Components 75
Caching 77
First-Level Caching 77
Second-Level Caching 78
Caching Queries 79
Inheritance Strategies 79
Table-per-Class Strategy 79
Table-per-Subclass Strategy 83
Table-per-Concrete-Class Strategy 85
Table-per-Concrete-Class Strategy Using XML mapping 85
Filters 87
Creating Filter Definitions 87
Enabling Filters 88
Relationship Owner (aka Inverse Attribute) 89
Cascading Entities 89
Summary 91
7. Hibernate Query Language. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Working with the Query Class 93
Fetching All Rows 94
Pagination 96
Retrieving a Unique Record 96
Named Parameters 96
Using the IN option 97
Positional Parameters 98
Aliases 98
Iterators 99
Selects 99
Aggregate Functions 100
Updates and Deletes 101
Criterias 101
Named Queries 102
Native SQL 104
Table of Contents | vii
Summary 104
8. Java Persistence API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Hibernate and JPA 106
Persistence Context 106
EntityManagerFactory 108
EntityManager 109
Persisting Objects 110
Saving and Querying Entities 110
Summary 111
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
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