Java developers

I have some very basic classes. They only have get/set methods.

however, I need to populate the variables in a loop. An array would deal with this easily if I knew how many times the loop would be repeated but I do not have this information.
How can I do this? I was going to use a vector but it looks more troublesome that in c++ (which I'm more used to).

Suggestions?

At work we have to keep the clients in mind.
We do middleware. So at any given time we will have two versions of our software running.
When we release a new version, we deprecate and remove from service the oldest.

So here is what we have resorted to:
We deploy the JNDI name with a version prepended to the front.
The clients (looking for the newest version with our changes) then look up that new JNDI, etc...

Anyone else run into this issue and do they have any great suggestions rather than resorting to these funny JNDI tricks?

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