entityManager.persist(participant);
}
@Override
public Participant update(Integer id, Participant participant){
Participant oldParticipant = findById(id);
// oldParticipant.setLecture(participant.getLecture());
oldParticipant.setStudent(participant.getStudent());
oldParticipant.setValue(participant.getValue());
return entityManager.merge(oldParticipant);
}