I'm facing what I think is a simple problem with Hibernate, but can't solve it (Hibernate forums being unreachable certainly doesn't help).
I have a simple class I'd like to persist, but keep getting:
SEVERE: Field 'id' doesn't have a default value
Exception in thread "main" org.hibernate.exception.GenericJDBCException: could not insert: [hibtest.model.Mensagem]
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
[ a bunch more ]
Caused by: java.sql.SQLException: Field 'id' doesn't have a default value
[ a bunch more ]
The relevant code for the persisted class is:
package hibtest.model;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.InheritanceType;
@Entity
@Inheritance(strategy = InheritanceType.JOINED)
public class Mensagem {
protected Long id;
protected Mensagem() { }
@Id
@GeneratedValue
public Long getId() {
return id;
}
public Mensagem setId(Long id) {
this.id = id;
return this;
}
}
And the actual running code is just plain:
SessionFactory factory = new AnnotationConfiguration()
.configure()
.buildSessionFactory();
{
Session session = factory.openSession();
Transaction tx = session.beginTransaction();
Mensagem msg = new Mensagem("YARR!");
session.save(msg);
tx.commit();
session.close();
}
I tried some "strategies" within the GeneratedValue
annotation but it just doesn't seem to work. Initializing id
doesn't help either! (eg Long id = 20L
).
Could anyone shed some light?
EDIT 2: confirmed: messing with@GeneratedValue(strategy = GenerationType.XXX)
doesn't solve it
SOLVED: recreating the database solved the problem
Sometimes changes made to the model or to the ORM may not reflect accurately on the database even after an execution of SchemaUpdate
.
If the error actually seems to lack a sensible explanation, try recreating the database (or at least creating a new one) and scaffolding it with SchemaExport
.