JTA事务：如果发生异常但未在事务上调用回滚，该怎么办？

Question

We have some third party code wherein they do the following

1. List item

   Create a User Transaction eg

     txn = (UserTransaction)ctx.lookup( "UserTransaction" ); txn.begin( ); 

2. Do some work persisting to the database (via JPA) to a MySQL database

3. txn.commit()

They have Exception blocks but NONE of them call txn.rollback . Good coding practice says they NEED to call rollback if an exception occurs but my question is If the txn is not committed, and an exception occurs what is the negative effect of them NOT calling rollback?

Answer 1

The transaction stays active, until you either commit() or rollback() it. It will continue to hold locks and you may end up blocking your application (database, actually).

Answer 2

IMO JTA事务最终应超时（基于set或默认transactionTimeout），并应自动回滚。