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JPA and transactions

So I was working with JPA and transactions.
Consider the following:
In bean 1, with implicit TX 1, managed entities are loaded/created,and returned
in bean 2, with implicit TX 2, entities are modified
in bean 3, with NO TX, bean 1 is called, and the results are passed to bean 2.
and bean 4 is similar to bean 3, but with it's own transaction, TX3

What happens when bean 3 finishes: are the entities updated?
What happens when bean 4 finishes, are the entities updated?
The answer to this is simple; entities are managed through a persistance context. That context is tied to the transaction. So in bean 2, there is a difference. When called from bean 3, it runs in a different transaction then bean 1, and thus a different persistance context, and thus the entities are not managed 'by this transaction'.When called from bean 4, it all runs in the same transaction, TX3, and the results are persisted.

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