Question about Spring transaction propagation

I have a question about Spring transaction propagation.

Suppose I use @Transactional(propagation = Propagation.开发者_如何学PythonREQUIRED) to annotate a method m1(). When execution logic enters m1(), if there is already a transaction, m1() will use that one. When after m1(), what about the transaction? It will end or still remain open? (if I call m1() in another method, and after the invocation there is still other things to do).

In summary, I want to know when exiting an annotated method, the transaction ends or still remains open?

Great thanks.

Propagation.REQUIRED (documented here) will create a new transaction (if none exists for the current thread), or will join an existing transaction (if one exists).

When the method exits, then the transaction will be completed (if entering the method caused a transaction to be created), or will leave the transaction open (if a transaction already existed when the method was entered). In other, words, it's symmetrical, and will leave the thread's transactional state in the same state it was before the method was entered.