@Transaction annotation in dao or service layer ?

[everson santos]

where is the best approach to put @Transaction annotation ? dao or service layer ?

 

//dao
@Transactional(propagation = Propagation.REQUIRED)
	public void save(T entity) {
	        getEntityManager().persist(entity);
	}


//service
@Transactional(propagation=Propagation.REQUIRED)
	public void save(T entity) {
                            //some business rules
	         genericDao.save(entity);
	}
   

[David Newton]

Depends.

Personally, I make my services transactional, my DAOs not--that way I don't need to nest transactions inside a service if I use multiple DAO calls. Of course, I also make my services implement the same interface my DAOs do, which some people find very annoying and redundant :)

[Gregg Bolinger]

Services and only when necessary.

@Transactional(propagation=Propagation.REQUIRED)  
public void save(T entity) {  
    //some business rules  
    genericDao.save(entity);  
}  

This is a total waste of a transaction since no other db writes are being made.