Simple project that shows how the JTA EntityManager is behaving in scope of JTA transactions
when it's created using EntityManagerFactory.
It shows few possible way how to use it. E.g. the EntityManagerFactory creates EntityManager:
- in place where there is a surrounding JTA transaction,
- in place where there is no surrounding JTA transaction,
- with manually join to the running JTA transaction,
- that spans across multiple JTA transactions.
All of the examples uses the UserTransaction interface, so it uses Bean Managed Transactions (BMT).
It's done just to easier show the described above bahavior - all of the described features are also available in
Container Managed Transactions (CMT). The most important fact is - we're talking about JTA EntityManagers -
we're not dealing with the resource-local EntityManagers.
By default the application exposes 2 REST endpoints:
-
http://HOST:PORT/emf-jta/rest/execute - invokes one of the defined methods and returns the list of persisted objects (so you can see if the method succeeded or not); remember to restart / republish the application after testing new method as the database should be cleared.
-
http://HOST:PORT/emf-jta/rest/cdi - invokes the CDI-related test (injection of request-scoped EntityManager)