FindByPK creates too many instances

Question

Hi all,
When using JBoss (I don't know other servers behavior) the findByPrimaryKey method creates a "home instance".
I think that JBoss need a "home instance" for finder methods and it could create only one to do that, but, in fact, it creates a new instance for each call and doesn't reuse it.
For example:
Integer pk = new Integer(1);
First findByPrimaryKey(pk): 2 instances created (Home instance and Bean instance)
Secound findByPrimaryKey(pk): 1 instance created (Home instance)
Third findByPrimaryKey(pk): 1 instance created (Home instance)
The ejbLoad method is called only on the first call (it's my configuration).
Any idea?
Thank you,
Denis.

Answer 1

Hi Denis,
Check your deployment descriptor - maybe you've
mistyped the remote interface for the home interface.
If I'm not mistaken, finder methods should return
remote, not home interfaces.
DimitarI think Denis meant a new HomeImpl (or whatever it's called) instance is created each time in the container to receive the home.findByPrimaryKey() request.
As such requests are stateless, one would expect the container to direct several of them (at least when they are serial and not in parallel) to only one instance of HomeImpl.
But it's a container decision. The container is free to instantiate a pool of HomeImpl, or one HomeImpl for each request,...
As far as EntityImpl instances go, it's not surprising that only one instance is created and that ejbLoad() is called only once, as long as the instance created first is still alive and active.
Not surprising but not obvious either : the container would be free to create several instances representing the same entity, provided it ensures transactionality (that seems one way of ensuring isolation of concurrent container-managed transactions on the same entity).
So in general one shouldn't rely on the instantiation of the Java object representing the implementation of a Home or a Remote as it may vary per container.
Now I think Denis' concern may be : does such an approach of creating a HomeImpl instance each time scale?