What is the differences when setup the TaskSessionSpringFactoryImpl using the following options?

(Option 1)    taskSessionFactory.setEntityManager(taskSharedEntityManagerBean().getObject());

(Option 2)    taskSessionFactory.setEntityManagerFactory(taskEmf());

What is the points in each case? Do they affect the scope of the underlying EntityManager used ? (ie when will the EntityManager closed)

PS :  I use Spring 's java configuration instead of XML to define the spring bean , so taskEmf() represent a bean of the task 's emf and taskSharedEntityManagerBean() is a SharedEntityManagerBean factory bean that builds SharedEntityManager