David Blevins wrote:
On Apr 1, 2009, at 1:24 PM, Martin Uhlir wrote:
assume, I have two (very similar) web applications (let's call them A
and B) which uses EJB as backend. The question is, how I can achieve,
that the application A stores its data to a database SchemaA, while
the application B stores its data to database SchemaB, while both
applications use the same EJB module (storing the data from A and B
is done via the EJB)? I want to avoid running (developing) two EJB
modules with the same functionality.
So is it somehow possible to achieve this just with some kind of
configuration or is there any other way how to solve this?
Note that the web applications will run on one server, while the EJB
on a different one.
Hi Martin,
No way to do this as far as I know. Even assuming you did something
very low level like wrapped the factory that creates the DataSources
so that the DataSource you create depends on some kind of thread state
which you set on in coming requests from webapp A or B, it still would
quickly fall apart due to things like connection pooling.
Is there some kind of overhead to deploying the application twice that
you'd like to avoid? Note with the right descriptors you wouldn't
need to modify the code at all. Might be some features we can add
there to eliminate any concerns.
-David
Hello David,
thank you for quick reply. Well, first my thought was, that it could
save resources on the server, because I expect to have even more these
similar web applications, so it seemed a bit pointless to me to have 10
times exactly the same EJB module deployed on the server.
Well, now arise a question, is it possible to deploy the same EJB module
(the same classes, same packages) 2 times, 3 times, ..., 10 times onto
one server? Won't the server be "confused" to have more the same classes
deployed on it? How can then the client applications A, B, C etc.
differentiate which particular EJB module (with the suitable
configuration files to access the proper db) they want to work with?
Martin
