[Springframework-developer] wrapping an interceptor and Hibernate specific TransactionProxyFactoryBean

[Colin S. <col...@ex...>]

I was using the TransactionProxyFactoryBean with the 
HibernateTransactionManager, but when I switched to the 
JTATransactionManager, got bitten by the fact that I no longer had 
anything creating a Hibernate session and binding it to the current 
thread, as HibernateTransactionManager used to do by default.

One verbose solution would have been to have gone back to the old 
ProxyFactoryBean mechanism for handling transactions, and just stack a 
HibernateInterceptor in front of the transaction interceptor.

I decided instead to make a Hibernate specific verison of 
TransactionProxyFactoryBean. All it does is take a new 
HibernateInterceptor property, and in afterPropertiesSet add the 
interceptor before the transaction one (however, unlike the transaction 
one, it will execute on all invocations, since you may want to run some 
methods with a hibernate session, but no transactions.
        // allways invoke the Hibernate Interceptor
        addInterceptor(hibernateInterceptor);
        ... existing code to set up the Transaction interceptor

Now my questions:
1: is it worth checking something like this in? I made a cut and past 
copy of TransactionProxyFactoryBean, and added the new property and 
modified the afterPropertiesSet. Obviously, I could also have just 
subclasses the existing class and overriden afterPropertiesSet. That's 
probably a better choice, but maybe a bit more dangerous if something 
changes in the parent method which is no longer called at all.
2: is there a better way of doing this? I supposed I could have wrapped 
the proxy in another proxy to add the hibernate interceptor. This would 
not have required any code changes, but would have made for a lot more 
typing in the context.  Another option would be to add optional before 
and after, 'always invoke' interceptor properties to the 
TransactionProxyFactoryBean, so something like this can be added.

Regards,
Colin