Hey,

i know that this is not the best place , but i am using Jboss with hibernate and this design issue is relevant to a lot of technology, also this forum have the best writers.


My client is a swt client that runs on machine A and the server is a J2ee server that runs on machine B.
We use facade design pattern and the API are exposed to the client as a stateless session bean.

The user does some configuration changes.
for change (like add new components ... ) we need to go to the server in order to create or edit the component (the client doesn't have the knowledge how to do this)
in the end of the configuration process the user may press on the persist button and all the changes need to be persist.

The concept that I need to implement is similar to the concept of editing word document all the changes are saved in temporal document until the user click on save or close the document.

As I see it I need long transaction here, but stateless doesn't support in long transaction and there are a lot of problems (time out and etc) in a long transaction.
I have to save those "temporal configurations" to the DB, because I need to get id for these configurations and other operations.

Does any one have an idea how to implement it?

It is important to remember that if the user edit an existing component other user don't see those changes unless he press on the save button. This scenario can lead to conflict.

Thank you.
Any idea will be welcomed.

I am not sure I see the problem. It doesn't matter where the component is instantiated, if it has to be instantiated in some server-side factory method, that is OK. There is nothing requiring you to actually persist the entity at that point. You can return a transient entity as well as a detached entity to the client. The client can continue to define the component and when they are ready to persist, you simply save the entity on the server-side.

on the realation between objects.