On Jul 6, 2009, at 10:28 AM, BenLeino wrote:
Hi there,
I am running into real trouble since one week, and I am afraid if
someone
could help me:
I have several EAR projectes including 1 EJB and one WAR projetc.
The EJB
encapsulates the business logic (entities, EJBs and certain JOBs anf
functions). The WAR is reponsible for managing user interaction
along this
business case.
Lets say I have "Items, Sales and Purchase" as three different
projects.
Now I have the problem that a function in "Items" needs information
from
"Sales" and Pruchase". And one function in Sales needs information
from
"Items" and "Purchase". Now i have a dependency cycle.
What is the best design pattern for this without loosing the business
choherence within the EAR packages (this one only for items, this
for sales
egtc.).
As a solution I made a big "DataModel.jar",which contains all EJB
remote
interfaces and alle entity POJO classes. So all dependency
references go
over that jar, and binding takes place with @EJB and the JNDI name.
But geronimo can't cope with that. It trries to validate @EJB
Annotation
within the web container at runtime and fails if the EJB istn't
there (GBEAN
Serialization Error). And some EJBs are not "injectable". Always when
OpenEJB tries to start them i get a Proxy NoClassDeffError.
You don't really explain how much the projects are intertwined. Lets
look at the jpa entities first. If you can separate them into 3
projects so the entities from each project can go in a different
database instance without losing any foreign key constraints then your
organization is plausible. If you lose foreign key constraints by
such separation, then IMO you only have one jpa project and should
combine all the entities in one java project.
If you really can come up with 3 independent jpa modules then I think
you can solve the problem with a interface jar containing the ejb
interfaces and interfaces for the jpa entities to implement. You'd
need to put this jar in its own classloader and have the javee
projects depend on it.
If you can't come up with 3 separate jpa modules then I rather doubt
you'll be able to have 3 separate ejb modules. You could put the jpa
stuff in its own jar but each dependency on it from an ejb module
will load a separate persistence unit, even within the same ear.
Would it be at all plausible to have the ejbs + entities deployed as
one javaee app/geronimo plugin and the web interfaces each deployed as
a separate javaee app/geronimo plugin depending on the ejb app? I'm
not sure how @Ejb annotations work across plugin boundaries... they
ought to be able to work, but I haven't tried it recently.
thanks
david jencks
Some help is really apriciated.
Thanks in advance,
Tim
--
View this message in context:
http://www.nabble.com/Solving-Dependency-Issuses-tp24359601s134p24359601.html
Sent from the Apache Geronimo - Users mailing list archive at
Nabble.com.
