Hibernate error persists an entity in @PostPersist method

I have a weird error of double insert in the DB. I have the following classes:

TestEntity - entity with a @PrePersist and a @PostPersist methods.
Auditoria - audit entity
Dataset - interface of DatasetBean
DatasetBean - Stateless bean which implements Dataset
DatasetFactory - instance an EJB of Dataset (lookup)

I put the problem in a junit test (I'm using embedded Glassfish):

@Test
public void test() throws NamingException {
    Dataset<TestEntity> dataset = this.lookupBy(DatasetBean.class);
    Assert.assertNotNull(dataset);

    TestEntity t = new TestEntity();        
    t.setName(UUID.randomUUID().toString());

    dataset.insert(t);
    System.out.println("end");
}

The flow of the test is the following:

After gettin a Dataset object, I try to insert a TestEntity object

@Stateless @EJB(name = "...", beanInterface = Dataset.class) public class DatasetBean implements Dataset {

@PersistenceContext(type = PersistenceContextType.TRANSACTION)
private EntityManager entityManager;

@Override
public void insert(T entidade) {
    LOG.info("Inserting: " + entidade);
    entityManager.persist(entidade);
}
//...

}

Using the DatasetFactory, I try to insert an Auditing entity in a @PostPersist method of the TestEntity

public class DatasetFactory { public static Dataset createDataset() { try { return (Dataset) new InitialContext().lookup("..."); } catch (Exception ex) { throw new RuntimeException(ex); } } }

@Entity public class TestEntity implements MyEntity { @Id private Integer id; private String name; // sets and gets
```
@PrePersist
public void fillId() {
    if (getId() == null || getId() == 0) {
        Dataset d = DatasetFactory.createDataset();
        Integer i = (Integer) d.fetchJPQLFirstResult("SELECT MAX(te.id) FROM TestEntity te");
        if (i == null || i < 100) {
            setId(100);
        } else {
            setId(i + 1);
        }
    }
}  

@PostPersist
public void audit() {
    Dataset<Auditing> dataset = DatasetFactory.createDataset();
    // dataset.getEntityManager().clear();
    Auditing auditing = new Auditing();
    auditing.setIdEntidade(String.valueOf(this.getId()));
    dataset.insert(auditing);
}
```
}

@Entity public class Auditoria implements MyEntity { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Integer id; private String idEntity; //sets and gets }

public interface MyEntity extends Serializable { Integer getId(); }

Log:

INFO: embedded was successfully deployed in 47.154 milliseconds. PlainTextActionReporterSUCCESSDescription: deploy AdminCommandApplication deployed with name embedded.

2012-01-06 02:56:54,826 [main] INFO com.joaosavio.model.db.DatasetBean (DatasetBean.java:30) - Inserting: TestEntity{id=null, name=ea5c2af4-0ca7-48a2-a82a-dbf582c570a9}

Hibernate: select max(testentity0_.id) as col_0_0_ from TestEntity testentity0_

Hibernate: insert into TestEntity (name, id) values (?, ?)

2012-01-06 02:56:56,344 [main] INFO com.joaosavio.model.db.DatasetBean (DatasetBean.java:30) - Inserting: Auditoria{id=null, idEntidade=100}

Hibernate: insert into TestEntity (name, id) values (?, ?)

2012-01-06 02:56:56,350 [main] WARN org.hibernate.engine.jdbc.spi.SqlExceptionHelper (SqlExceptionHelper.java:143) - SQL Error: 2627, SQLState: 23000

2012-01-06 02:56:56,352 [main] ERROR org.hibernate.engine.jdbc.spi.SqlExceptionHelper (SqlExceptionHelper.java:144) - Violation of PRIMARY KEY constraint 'PK_TestEntity_76818E95'. Cannot insert duplicate key in object 'dbo.TestEntity'.

06/01/2012 02:56:56 com.sun.ejb.containers.BaseContainer postInvoke

WARN: A system exception occurred during an invocation on EJB DatasetBean method public void com.joaosavio.model.db.DatasetBean.insert(java.lang.Object) javax.ejb.TransactionRolledbackLocalException: Exception thrown from bean ...

Caused by: javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: Violation of PRIMARY KEY constraint 'PK_TestEntity_76818E95'. Cannot insert duplicate key in object 'dbo.TestEntity'. ...

Caused by: org.hibernate.exception.ConstraintViolationException: Violation of PRIMARY KEY constraint 'PK_TestEntity_76818E95'. Cannot insert duplicate key in object 'dbo.TestEntity'.

Considerations:

Relying on the fact that everything works fine if I clear the entity manager before the insertion of the Auditing entity (comented code in @PostPersist method in TestEntity), I believe that the TestEntity is getting stuck in the transaction.

What am I doing wrong???

Solution

Ive seen a very similar issue once.... You should ---

Be very careful with @PostPersist ! hibernate bean persist or save actions ARE NOT the same as database Insertions!

The problem is likely that are that you are assuming that @PostPersist methods are invoked after the data has been inserted .... However , that is not always the case! PostPersist methods are callbacks BUT they are not callbacks from the database !!! As you know - hibernate may not have committed your transaction And flushed it completely. if you try to use PostPersist to coordinate barriers between your database transactions, you are making a mistake.

The solution is to do all your inserts in a single properly planned and managed transaction, with keys and cascades worked out so that hibernate will be able to organize the inserts for you in the right way--- or just hardcode a stored procedure to do the work for you.

I think you might be merging stateful and stateless transaction logic here.