AFAIK no such thing exists as of now. Not sure about others, but  
luckily I was spared from any such migrations. Would be nice if  
somebody with a real experience could document what they needed to do.
My guess on the high level approach would be to start with reverse  
engineering the DB schema, and generating Cayenne superclasses with  
Hibernate current classes mapped as subclasses. And then fix the API  
calls manually. But I am sure there are quirks for non-flat mapping  
scenarios (inheritance and such). Also you may need to rethink some  
app concepts... E.g. Cayenne doesn't force transactions on you unless  
you *must* have them... things like that.
Andrus
P.S. When I was about to hit "send", I noticed a message from Scott  
Anderson, based on the same idea.
On Feb 20, 2008, at 9:08 PM, Thomas Bernhard wrote:
>
> Hi,
>
> Is there a migration guide from Hibernate(especially 2.x.x) to Cayenne
> (whatever version)?
>
> Or even better, is there maybe some tool that helps this even further?
> (when moving from Velocity to Freemarker there's a tool to automate  
> this,
> and even other frameworks have "migration" tools to help uses move  
> from the
> concurrence :) )
>
> Thank you,
>
> Tom.
> -- 
> View this message in context: http://www.nabble.com/How-to-migrate-from-Hibernate-to-Cayenne--tp15596160p15596160.html
> Sent from the Cayenne - User mailing list archive at Nabble.com.
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