Question

I´m having a problem with nativeid and i don´t know if i am doing right.

I have a class called Aircraft that has an generated id. But its native id is the serial number(Integer) and Model( a custom class) like below:

public class Aircraft{

@Id @GeneratedValue(strategy=GenerationType.AUTO,generator="COD_NS_AENV")
@Column(name="COD_NS")
private Integer id;
@Column(name="NUM_IDENT_NS_AENV")
@NaturalId
private Integer serialNumber;
@ManyToOne
@NaturalId
private Model model;

.
.
.
}

I load this class from an XML and save into the database, like this:

.
.
.
Aircraft aircraft= (Aircraft)xstream.fromXML(reader);
Session session =  HibernateUtil.openSession();
Transaction t = session.beginTransaction();

session.saveOrUpdate(aircraft.getModelo());
session.saveOrUpdate(aircraft);
t.commit();
session.close();

It works fine for insert,but my problem is when I execute this code again with the same information, Hibernate inserts another aircraft. I want that Hibernate only updates the current registry.

I overrided the method equals() to test the serialNumber and Model attributes but it is never called.

I don´t know how to make Hibernate understand that an object with serialNumber and model are the NativeId.

Thanks in advance!

Alexandre

Answer 1

Most likely Hibernate just uses @Id property and generates new value every time. That happens because you read your object from XML and id is not in XML, I assume. I don’t think natural id will coexist well with surrogate autogenerated id. And for saveOrUpdate Hibernate will just look at id to determine if object is new.

Here is more details on Hibernate forums.