java - @Transactional method called from another method doesn't obtain a transaction

Question

In Spring, a method that is annotated with @Transactional will obtain a new transaction if there isn't one already, but I noticed that a transactional method does not obtain any transaction if it is called from a non-transactional one. Here's the code.

@Component
public class FooDao {
    private EntityManager entityManager;

    @PersistenceContext
    protected void setEntityManager(EntityManager entityManager) {
        this.entityManager = entityManager;
    }

    @Transactional
    public Object save(Object bean) {
        return this.entityManager.merge(bean);
    }

    public Object saveWrap(Object bean) {
        return save(bean);
    }
}

@Component
public class FooService {
    private FooDao fooDao;

    public void save(Object bean) {
        this.fooDao.saveWrap(bean); // doesn't work.
        this.fooDao.save(bean); // works
    }
}

saveWrap() is a regular method that calls save() which is transactional, but saveWrap() won't persist any changes.

I'm using Spring 3 and Hibernate 3. What am I doing wrong here? Thanks.

Answer 1

It is one of the limitations of Springs AOP. Because the dao bean is in fact a proxy when it is created by spring, it means that calling a method from within the same class will not call the advice (which is the transaction). The same goes for any other pointcut