I read the below explanation on JTA transaction from Mastering EJB3.0 written by Sriganesh,brose,silverman
JTA transaction always begins & ends externally to the JTA entity manager.
Beans and Container, in case of bean-managed and container-managed transactions, respectively,
will begin and end the JTA transactions;
they make entities a part of their active transactions by enlisting the entity manager's persistence context.
The entity manager, therefore, only participates in an already active JTA transaction; it doesn't actually begin or commit a JTA transaction on its own.
Hence, there is no mechanism to specify the transactional behaviour of the entities. Their transactional behaviour is completely dependent on the caller
I have some doubts in the above.
1. why do they mention about JTA in container-managed transaction. do they mean a distributed transaction environment ?
2. what do they mean by "transactional behaviour of the entities" in this context ?
I am totally confused with the explanation. It will be good if someone can explain me what they are trying to arrive at ?