entitymanager multiple insertion

[Laedislaw]

Followng method serves 2 purpose (saves and updates). Problem when updating a record - multiple inserts occur. What could be the possible causes? Thanks

line: em.merge(aEntropy);

@Stateless
@Service("jpaEntropyService")
@Repository
@Transactional
public class EntropyServiceImpl implements EntropyService {
	private Log log = LogFactory.getLog(EntropyServiceImpl.class);
	@PersistenceContext(type=PersistenceContextType.EXTENDED)
    private EntityManager em;

...
@Transactional
	public Entropy save(Entropy aEntropy) {
		if(aEntropy.getEntropyId() == null){ //New Entropy
			log.info("Inserting new Entropy");
			em.persist(aEntropy);
		}else{ //Update Entropy
			em.merge(aEntropy); //<--- here
			log.info("Updating Entropy Record");
			
		}
		log.info("Entropy Saved with id: "+ aEntropy.getEntropyId());
		
		return aEntropy;
		
	}