Implementing the Interceptor interface requires me to map Object arrays of current/future state onto the properties of my persistent objects. Why represent the state as Object arrays, rather than, say, a Map from (property name)->(property value), similar to the Distributed Objects pattern? or perhaps even instances of the persistent class?

http://www.hibernate.org/161.html

Has anyone developed any good patterns to assist/automate this mapping? To date, I have simply implemented some utility methods that build up a maps of (property name)->(Object[] index) for each persistent class... I am betting that the order of the properties in the Object array are static once the mapping files are loaded.

Thanks!

I have implemented something like this. Check out http://hibernate.bluemars.net/156.html for details (specifically the stuff relating to the PropertyDelta interface towards the end).

Generally maps will not work here. There will be times when you'll need both the original value as well as the new value. Kind of hard to do that with a simple Map structure.

I glanced at that pattern before, but didn't appreciate it -- thanks for "helping" me take a closer look.

Indeed, a map is not itself useful for maintaining deltas between new/old state. But two maps would work nicely for this :)

I suppose it just depends on the use case/access pattern. If the Interceptor is just going to iterate over all state and doesn't actually care which property it is (just it's type or whatever), then the Object[] arrays are fine. But if you want to correlate the new/old values back to specific properties, having a map seems like it would be a lot more useful.