with Spring MVC. I have a method for get the game and update but when it goes to update it gives an error, this is the code:

HomeController.class

@Transactional@RequestMapping(value = "/partida/{idPartida}", method = RequestMethod.GET)public String getPartida(@PathVariable("idPartida") long idPartida,        Model model) throws IOException {    Partida p = ServicioAplicacionPartida.getPartida(entityManager,            idPartida);    if (p.getJson() == null) {        p.inicializarPartida(entityManager);        ServicioAplicacionPartida.update(entityManager, p);    }

GameDAO.class

@Transactionalpublic static Partida update(EntityManager entityManager, Partida p) {    try {                       Query q = entityManager.createNativeQuery("update Partida p SET p.json=:json where p.id=:id");        q.setParameter("json", p.getJson());        q.setParameter("id", p.getId());        q.executeUpdate();        return entityManager.find(Partida.class, p.getId());    } catch (Exception e) {        e.printStackTrace();        return null;    }}

The error occurs when the line "q.executeUdate()" is executed, here it is:

javax.persistence.PersistenceException: org.hibernate.exception.DataException: could not execute statement And this is the server error: Estado HTTP 500 - Request processing failed; nested exception is org.springframework.transaction.TransactionSystemException: Could not commit JPA transaction; nested exception is javax.persistence.RollbackException: Transaction marked as rollbackOnly What can i do to fix it?

You have annotated controller and DAO methods as @Transactional, it is not correct as @Transactional can be inherited to the inner methods. Usually transaction should start at service layer.

Try adding these parameters to @Transactional annotation and remove it from either Controller or DAO.:

@Transactional(readOnly = false, propagation = Propagation.REQUIRED, rollbackFor=Exception.class)

and try:

propagation = Propagation.REQUIRES_NEW