Hi there,

I'm using JPA via the Hibernate EM to return the result of a query as a SOAP response. I'm naturally getting a "failed to lazily initialize a collection" type of exception when attempting to serialise my response given that my entity manager has been closed.

I'm wondering if there's a way of forcing a deep eager fetch on the result before I close my entity manager.

Oh, I should add that at the time that I make the request, it is unknown how deep the resultant object graph will be i.e. A may have a child B, which may have a child C, which may have a child D etc. This means that I don't know what to eagerly fetch in advance i.e. JOIN FETCH is probably not applicable?

I'm sure that this is JPA 101, so I apologise in advance for that. I'm kind-of stumped though.

Thanks for any help.

Cheers,
-C

I've managed to figure this one out... if I serialise the object graph myself prior to closing the entity manager then I'm guaranteed that the graph has been entirely fetched. I can additionally pre-empt what will be lazily fetched with JOIN FETCH of course.

It'd be great for JPA to have a little more control over the fetch strategy on a dynamic basis... still, JPA/Hibernate rock!

Cheers,
-C

You could use Hibernate.initialize(..).



Farzad-

Thanks for that - I was looking for a JPA style of answer but nonetheless appreciate your response.

The problem here is that JPA does not cover everything. Therefore, you could expect to have vendor specific code here and there and that's fine. You would be able to replace vendor specific codes as the API evolves.


Farzad-