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From Srinivasan Krishnamoorthy <srinivasan.kr...@live.com>
Subject Detach and Attach with XML serialization
Date Sun, 04 Oct 2009 11:15:34 GMT

Hi,
 I have an issue with detaching and attaching the entities when serialized as XML.
I have an entity which is serialized as XML and sent to client in a stateless fashion. (I
have not serialized some relations)
When the XML is sent back to me I have to attach/merge it and do an update.
I can pass on the Id and version and get it back from the client. But not the Detach state
field Object.
So I have 2 solutions below.

Solution 1
 After receiving the updated XML, do a find with the primary key and update the values and
persist.

 Drawbacks:
 1. I have to do a find for every update.
 2. I have to copy each and every variable of the object. This I need to do for every object
that I use.
 3. I use JAXB for constructing the java object, but not able to merge it directly because
I don't have detach state field info.

Solution 2 (Not sure if this will work, havent tried it)
 After the entity is detached, store the detach state field (serialized Object) in a database
with Id and classname as composite primary key.
 Before attach, fetch this Object from DB and set it on to the field, and then do an attach.

 Drawbacks:
 1. DB operation is required for detach and attach.

 Advantage:
 Solution is generic. (if it works :-) )

 Please advise me on the best choice, or if there is a better way, please suggest me the same.


Best Regards,
Srinivasan Krishnamoorthy
 
 		 	   		  
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