EntityManager em = entityManagerFactory.createEntityManager();
em.getTransaction().begin();
for (int i = 0; i < contactsFirstNameData.length && i < contactsLastNameData.length && i < contactsEmailData.length; ++i) {
ContactEntity contact = new ContactEntity(contactsFirstNameData[i], contactsLastNameData[i], contactsEmailData[i]);
em.persist(contact);
System.out.println("Persisted: " + contact.getId() + " " + contact.getFirstName() + " " + contact.getLastName());
}
em.getTransaction().commit();
}