[appengine-java] Re: Problem with query - jdo

[lp]

 The persistence layer uses lazy-load approach, so when in jsp it tries to
 access to entities extracted from the database it throws exception because
 the persistence manager is just closed.
 So, how to avoid this problem?

so either use eager fetch... not a good idea for large objects.
OR
use a VTO pattern (http://java.sun.com/blueprints/patterns/
TransferObject.html) to populate ur presentation objects.
this enables the persistence layer transaction to be abstracted away
from presentation.

VTO pattern is more usefull.

-lp

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[appengine-java] Re: Problem with query - jdo

[coder]

I have understood the problem.

The persistence layer uses lazy-load approach, so when in jsp it tries to 
access to entities extracted from the database it throws exception because 
the persistence manager is just closed.
So, how to avoid this problem? I have to use DAO class or controller of them 
directly in jsp? Cannot i use in jsp the HttpSession to get the 
requested objects (putted in session by a servlet)?

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