Using remote EJB3 bean from multiple remote versions of Jbos

[henk53]

Hi,

I noticed that the Jboss AS client libraries, which are needed for a client to consume among others a remote EJB3 bean hosted by a Jboss AS server, are very specific to a specific version of Jboss AS.

E.g. if my client application has the client libraries for Jboss AS 4.2.2, it can not connect to a remote Jboss AS 4.2.3 instance. Likewise, a client that has the client libraries for 4.2.3 can not access a Jboss AS 5 instance.

Now my question is, what do I do if 1 application needs to access beans in both a Jboss AS 4.2.3 instance AND a Jboss AS 5 instance?

Slightly related to this: is there any way to programmatically detect the version of the client library and the remote server? When there is a mismatch in versions between the client and the server now, I get a very unhelpful bunch of exceptions. I would like to catch these and somehow inform my users about the exact version mismatch. E.g.

"This application has been equipped with the Jboss client libraries for Jboss AS 4.2.2. You are however trying to connect to a Jboss AS 4.2.3 server. Please downgrade your server or upgrade your client libraries"

[jaikiran]

See if this version matrix helps http://www.jboss.org/community/docs/DOC-10808

[henk53]

"jaikiran" wrote:
See if this version matrix helps http://www.jboss.org/community/docs/DOC-10808

That does help indeed. I now realize I misunderstood the situation: it's not that versions -always- need to match exactly, but there are compatibility ranges.

I did notice though that the 2 incompatibilities I found (Jboss 4.2.2 client with Jboss 4.2.3 server, and Jboss 4.2.3 client with Jboss 5 server), are not listed in the matrix.

[peterj]

I think that the idea of having an API to check the versions is a good one. I recall many years ago while developing a client/server app that one of my testers complained almost daily that the build was broken. After a few times of helping him and finding out that in each case he mismatched the client and server components, I added a method to the server that returned the version number, and had the client request the version number before doing anything else, and generating a decent error message if it did not like what it saw. That tester never complained again, though he did mention that he often got that error but now at least he knew what he did wrong and how to fix it.