I have a situation where I would like to use Hibernate to read objects from a database with no requirement to ever write them back. Furthermore, it would be helpful if the resulting objects were based on the standard java collection classes, with no Hibernate classes present in the resulting data structures.

Is this possible, or must I do a manual copy from one form to the other?

Many thanks for any advice.

AD[/b]

If you don't want to write them back, you can specify mutable=false which tells hibernate that they're read only.

Why do you care what the underlying implementation of the Collections are since it's best practice to code to interfaces and Hibernate provides data in java.util.Set, java.util.List collections etc...

Two main reasons (largely related to serialisation):

1) I want to be able to save them as XML files, using something like Castor, and it'd be easier to use the standard mappings 'out of the box'.

2) Ditto for serialisation in the context of a distributed cache.

I know that I can overcome this issue by writing my own mappings/serializers but I'm just lazy by nature ;-)

I'm not that familiar with Castor but it's hard for me to believe that it expects your Collections to be concrete classes (java.util.ArrayList, HashMap etc...) and not interfaces (java.util.List, Map, Collection etc...)

Hibernate also has built-in support for a variety of Cache implementations.

Castor is quite capable of serialising most standard beans. However, it expects to deserialise them into the same classes that it started from (it stores the class details as part of its serialision data). However, it is probably unacceptable for the deserialisation to create internal Hiberate classes - especially if this is done outside of a session, as might possibly be the case.

In the case of a distributed cache, the situation is even more extreme, since the remote cache instance on which the object is re-formed might not even have Hibernate installed.

I'm assuming from your response that my request is not supported, so I guess I'll have to write my own mappings & serialiser. Thanks for all your help in any case.

Regards,

AD

did you take a look at H3 xml support ? it might be enough for you so you dont need to use yet another tool ,)