Jersey, Guice and Hibernate - EntityManager thread safety

Question

I have used this tutorial them same way in my application: http://www.benmccann.com/hibernate-with-jpa-annotations-and-guice/

My app is JAX-RS web service which will

Answer 1

If it says that the transaction is already open, that means that it was open by another process and not closed ...

I suggest to use @Transactionl instead of Writing :

em.getTransaction().begin();

and

em.getTransaction().commit();
em.close();

That will manage the things for you ...

so for you it will be this way :

@Transactionl
@POST
@Path("/{id}")
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public void saveItem(){
     entityManager.persist(new Item());
}

Hope that's help