I'm using 1.0 rc1 with the PB API. I'm noticing that I don't have any isolation
between multiple brokers when caching is enabled. For example:
Object[] pk = new Object[] {new Long(42)};
Identity id = new Identity(Article.class, pk);
PersistenceBroker broker1 = PersistenceBrokerFactory.defaultPersistenceBroker();
broker.beginTransaction();
Article a1 = (Article) broker.getObjectByQuery(new QueryByIdentity(id));
a1.articleName = "My article";
// start a second transaction
PersistenceBroker broker2 = PersistenceBrokerFactory.defaultPersistenceBroker();
broker2.beginTransaction();
Article a2 = (Article) broker.getObjectByQuery(new QueryByIdentity(id));
// a2 is another reference to the same Article as a1
a2.unit = "kg";
broker2.abortTransaction();
broker.store(a1, ObjectModificationDefaultImpl.UPDATE);
broker.commitTransaction();
broker2.close();
broker.close();
The changes that I made on the aborted broker2 transaction end up getting persisted on
the broker1 transaction because they're sharing the same object reference. Similarly
changes made on other transactions are visible even before they're committed. In
general it doesn't look like I have any transactional isolation if caching is turned
on. I guess my gut expectation was that caches would be broker specific and there
would be communication between caches to coordinate invalidations on updates and
deletes.
So how do other people deal with this? I had thought maybe I could manage two
jdbc-connection-descriptors pointing to the same database, one with a cache used only
for reads and another with caching turned off used for updates but it looks like the
caching policy is global not on a per descriptor basis. Am I missing something
obvious?
