JAVA PERSISTENCE API (JPA)
5
Step 1 : Verify your Java Installation ....................................................................................................... 21
Step 2 : Set your Java Environment ......................................................................................................... 22
Step 3 : Installing JPA .............................................................................................................................. 22
Adding MySQL connector to the Project ................................................................................................. 27
5. JPA – ENTITY MANAGERS .................................................................................................... 29
Creating Entities ...................................................................................................................................... 30
Persistence Operations ........................................................................................................................... 34
Create Employee ..................................................................................................................................... 34
Update Employee ................................................................................................................................... 35
Deleting Employee .................................................................................................................................. 38
6. JPA – JPQL ........................................................................................................................... 40
Java Persistence Query language ............................................................................................................ 40
Query Structure ...................................................................................................................................... 40
Scalar and Aggregate Functions .............................................................................................................. 41
Between, And, Like Keywords ................................................................................................................. 43
Ordering ................................................................................................................................................. 45
Named Queries ....................................................................................................................................... 46
Eager and Lazy Fetching .......................................................................................................................... 50
7. JPA – ADVANCED MAPPINGS .............................................................................................. 51
Inheritance Strategies ............................................................................................................................. 51
Single Table strategy ............................................................................................................................... 51
Joined Table Strategy .............................................................................................................................. 58
Table per Class Strategy .......................................................................................................................... 66
8. JPA – ENTITY RELATIONSHIPS .............................................................................................. 74
@ManyToOne Relation ........................................................................................................................... 74
