Inconsistent JPA behavior using no transaction, propagation SUPPORTS and OpenEntityManager pattern

1
votes

We are using JPA (Hibernate 4) with Spring 4 managing the JTA transactions. To allow lazy initialization even when simply reading from the database without any transaction we added the "OpenEntityManager" pattern.

You can find a test case for these questions on GitHub https://github.com/abenneke/sandbox/tree/master/spring-hibernate4-transaction

We know that there is a difference between having no transaction synchronization at all and SUPPORTS synchronization. But the JPA behaviour seems to be inconsistent somehow:

  • If there is no transaction synchronization active, we get a TransactionRequiredException from Springs SharedEntityManagerCreator when trying to persist something using JPA.
  • If there is only a SUPPORTS transaction synchronization active, we don't get this exception and the persist request is silently ignored. This however is exactly the situation to avoid in the SharedEntityManagerCreator when creating the above exception.
  • If there is an "OpenEntityManager" pattern active, there is no exception also and the persist request is silently ignored as well.

In my opinion there is no real difference between these situations and I would expect to see this exception in all cases or none?

Thank you!

Update July 2015: I now raised this as an issue to Spring https://jira.spring.io/browse/SPR-13243

1
springhibernatejpatransactionsspring-transactions

1 Answers

0
votes

See:

http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/orm/hibernate3/support/OpenSessionInViewFilter.html

(OpenEntityManagerInViewFilter should work the same way)

NOTE: This filter will by default not flush the Hibernate Session, with the flush mode set to FlushMode.NEVER. It assumes to be used in combination with service layer transactions that care for the flushing: The active transaction manager will temporarily change the flush mode to FlushMode.AUTO during a read-write transaction, with the flush mode reset to FlushMode.NEVER at the end of each transaction. If you intend to use this filter without transactions, consider changing the default flush mode (through the "flushMode" property).

So with OEMIV and no transaction there is no Flush and so, no TransactionRequiredException.