Example 3. PersonDaoImpl
@Repository @Transactional(readOnly = true) public class PersonDaoImpl implements PersonDao { private EntityManager em = null; /** * Sets the entity manager. */ @PersistenceContext public void setEntityManager(EntityManager em) { this.em = em; } /** * Find persons. */ public Person findPersonById(Integer id) { return em.find(Person.class, id); } /** * Find persons using a start index and max number of results. */ @SuppressWarnings("unchecked") public Collection<Person> findPersons(final int startIndex, final int maxResults) { return em.createQuery("select p from Person p order by p.lastName, p.firstName") .setFirstResult(startIndex).setMaxResults(maxResults).getResultList(); } /** * Find persons. */ @SuppressWarnings("unchecked") public Collection<Person> findPersons() { return em.createQuery("select p from Person p order by p.lastName, p.firstName").getResultList(); } /** * Find persons by last name. */ @SuppressWarnings("unchecked") public Collection<Person> findPersonsByLastName(String lastName) { return em.createQuery("select p from Person p where p.lastName = :lastName order by p.lastName, p.firstName") .setParameter("lastName", lastName).getResultList(); } /** * Saves person. */ @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW) public Person save(Person person) { return em.merge(person); } /** * Deletes person. */ @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW) public void delete(Person person) { em.remove(em.merge(person)); } /** * Saves address to person. */ @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW) public Person saveAddress(Integer id, Address address) { Person person = findPersonById(id); if (person.getAddresses().contains(address)) { person.getAddresses().remove(address); } person.getAddresses().add(address); return save(person); } /** * Deletes address from person. */ @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW) public Person deleteAddress(Integer id, Integer addressId) { Person person = findPersonById(id); Address address = new Address(); address.setId(addressId); if (person.getAddresses().contains(address)) { person.getAddresses().remove(address); } return save(person); } }