Re: Request Factory Entity Relationships Lazy Loading

Hi

I had this problem as well. I haven't found perfect solution.. What I
have done is while retrieving data from the database so e.g. in
findEntity(Long id) method I am forcing persistent layer to return my
collection immediately:
Entity findEntity(Long id)
{
// open transaction, get entityManager etc.
// ...

Entity obj = entityManager.find(id);

// force retrival of collection
obj.getDonations().size();

// handle transaction and entitymanager etc.
//...
}

I will be very glad to find out how to make it in a better way:)

On Nov 18, 1:02 am, PJ Herring <pjh...@gmail.com> wrote:
> So I've been working on this problem with RequestFactory and Lazy
> Loading. I am using a Service Layer to deal with operations on Domain
> Objects. I ran into a problem when I was trying to "merge" an object
> with my Hibernate Domain layer. Hibernate was throwing a "lazy
> loading" error ("Failed to lazily initialize a collection"). The
> problem was when I fetched an object via RequestFactory it did not
> come with its relationships. So if I had a Donor with a collection of
> Donations, the Donations do not come with the initial fetch unless
> specified (i.e.
> requestFactory.donorRequest().fetch(id).with("donations")). When I
> removed the relationship from the Proxy Domain Object (so removing the
> methods getDonations and setDonations from the DonorProxy), I did not
> have this problem. The merge worked fine. Why is this the case?
>
> Second, if this is the case it would seem beneficial to remove
> relationships that you would normally want to lazy load from the
> proxies and just make an explicit call to load up the collection. So
> remove the getDonation and setDonation from the DonorProxy and when I
> need those donations just make a call with the donorId to get them.
> This seems counter intuitive to me, but seems also not like a terrible
> idea. Basically I am trading of between having to make explicit calls
> to load OneToMany relationships and being able to do merge's. AM I
> CRAZY?

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