How do I insert a lot of entities in a Play! Job?

In my application I have开发者_JS百科 to simulate various situations for analysis. Thus insert a (very) large amount of lines into a database. (We're talking about a very large amount of data...several billion)

Model

@Entity
public class Case extends Model {

    public String url;
}

Job

public class Simulator extends Job {

    public void doJob() {

         for (int i = 0; i !=) {

             // Somestuff

             new Case(someString).save();
         }
    }
}

After half an hour, there is still nothing in the database. But debug traces show Play inserts some stuff. I suspect it is some kind of cache.

I've tried about everything :

Model.em().flush();

Changes nothing.

Model.em().getTransaction().commit();

throws TransactionRequiredException occured : no transaction is in progress

Model.em().setFlushMode(FlushModeType.COMMIT);
Model.em().setFlushMode(FlushModeType.AUTO);

Changes nothing.

I've also tried @NoTransaction annotations everywhere :

• Class & functions in Controller
• Class Case
• Overriding save method in Model
• Class & functions of my Job

Getting quite desperate. Every kind of advice is welcome.

EDIT : After a little research, the first row appears in database. The associated ID is about 550.000. That means about half a million rows are somewhere in between my application and database.

---

Try

em.getTransaction().begin();
em.persist(model);
em.getTransaction().commit();

You can't commit a transaction before you begin it.

---

as per documentation, the job should have its own transaction enabled as Play request do, so that's not the issue. Try doing this:

for (int i = 0; i !=) {

  // Somestuff

  Case tmp = new Case(someString);
  tmp = JPA.em().merge(tmp);
  tmp.save();
}

The idea is that you add the newly created object to the EntityManager explicitly before saving, making sure the object is part of the "dirty objects" that will be persisted.

---

You need to instruct Play! when it should run your job by annotating your class with one of these annotations @OnApplicationStart, @Every or @On.

Please check Play! documentation on jobs