| This test suite is supposed to assert that when roll back happens, if the unsynchronized |
| persistence context have already joined the transaction, the persistence context will be cleared. |
| |
| From SPEC JSR338, chepter 7.6.1 Persistence Context Synchronization Type: |
| If a persistence context of type SynchronizationType.UNSYNCHRONIZED has been joined to |
| the JTA transaction, transaction rollback will cause the persistence context to be cleared and all |
| pre-existing managed and removed instances to become detached. |
| |
| One test case is involed: |
| 1. Persist a entity to the database, invoke joinTransaction method, and then roll back the transaction |
| assert the PC doesn't contain the entity any longer. |
| |
