How to start a transaction in JPA using entityManager

Question

I have started working on an application which uses spring, hibernate, JPA, SOAP webservices. Now there is a requirement that certain queries have to be run in a transaction

Answer 1

Try injecting EntityManagerFactory and then creating the EntityManager manually:

@PersistenceUnit
private EntityManagerFactory entityManagerFactory;

public boolean processBills() throws Exception{

   EntityManager em = entityManagerFactory.createEntityManager();

   EntityTransaction tx = null;

   Session session = null;

   try{

       session = em.unwrap(Session.class);
       tx = em.getTransaction();