I have a simple entity object:

@Entity
@Table
public class Equipment {
@Id @GeneratedValue
@Column(name = "EQUIPMENT_ID")
private int equipmentId

@Column
private String name
}

The way I am going about this is I am storing a list in memory of these objects (incrementing the id every time one is added). At the end I save to the database. This works fine pre hibernate.

I am now refactoring my code to use hibernate. I have the loads for other objects working fine. I and am cycling through the equipment list doing a session.save(equipment). Looking at the log this gives:
Hibernate: insert into Equipment (name) values (?)
and nothing gets saved. I thought it might be because the
@GeneratedValue have been generated by me but when I removed @GeneratedValue there was no change.

My requirements are:
- I need to built up equipment list in memory and not save to database until the end
- I need to have an id generated in memory (prior to saving) as my list will get accessed literally 100's of thousands of times.

Is there a smarter way to go about this?

Thanks, Tom.

Hibernate version:
hibernate-3.2.6.ga / hibernate-annotations-3.3.1.GA

Mapping documents:
done in hibernate.cfg.xml
<mapping class="mypackage.Equipment"/>

Code between sessionFactory.openSession() and session.close():
equipmentList.each { equipment ->
session.save(equipment)
}

Full stack trace of any exception that occurs:
No exception

Name and version of the database you are using:
MySql 5.0

The generated SQL (show_sql=true):
Hibernate: insert into Equipment (name) values (?)


Debug level Hibernate log excerpt:

<<Inserting entity: mypackage.Equipment (native id)>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractEntityPersister.java:2149)
<<about to open PreparedStatement (open PreparedStatements: 0, globally: 0)>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractBatcher.java:366)
<<insert into Equipment (name) values (?)>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractBatcher.java:401)
<<preparing statement>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractBatcher.java:484)
<<Dehydrating entity: [mypackage.Equipment#<null>]>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractEntityPersister.java:1997)
<<binding '"my equipment"' to parameter: 1>> Jul 3, 2008 12:03:11 PM DEBUG [main] (NullableType.java:133)
<<Natively generated identity: 409>> Jul 3, 2008 12:03:11 PM DEBUG [main] (IdentifierGeneratorFactory.java:72)
<<about to close PreparedStatement (open PreparedStatements: 1, globally: 1)>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractBatcher.java:374)
<<closing statement>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractBatcher.java:533)
<<allowing proxied method [beginTransaction] to proceed to real session>> Jul 3, 2008 12:03:11 PM DEBUG [main] (ThreadLocalSessionContext.java:300)
<<allowing proxied method [save] to proceed to real session>> Jul 3, 2008 12:03:11 PM DEBUG [main] (ThreadLocalSessionContext.java:300)
<<saving transient instance>> Jul 3, 2008 12:03:11 PM DEBUG [main] (DefaultSaveOrUpdateEventListener.java:158)
<<saving [mypackage.Equipment#<null>]>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractSaveEventListener.java:153)
<<executing insertions>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractSaveEventListener.java:244)
<<executing identity-insert immediately>> Jul 3, 2008 12:03:11 PM DEBUG [main] (AbstractSaveEventListener.java:297)

A simple groovy SSCCE demonstrates my lack of understanding with this issue:

Using the Equipment entity above:



As reported I get:

Hibernate: insert into Equipment (name) values (?)
Hibernate: insert into Equipment (name) values (?)

but nothing is written to the database. If I remove the @GeneratedValue nothing gets saved but I don't get the above inserts.

I would really appreciate someone pointing this Hibernate rookie in the right direction.

Tom.