I am designing a multi-tier application in which the User Interface interacts with Problem Domain objects, which interact with Data Management objects, which interacts with the database. This will be a multi-user application, so users will access the system via a username and password, which will be used, in part for database connections. Here is where I am running into problems - if my database connections require the username and password to access the database, how do I get this information down to the DM layer without passing it through the PD layer? I don't want the PD objects to be polluted with the notion of users or an underlying database. I know I can store any information I like in session variables, but how can the DM objects determine what session called them without session information being passed down through the PD layer? I've started looking at Enterprise Java Beans as a possible solution, but it seems like there is a lot of overhead there that I don't necessarily need. Thanks, and I look forward to your comments.
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Robert S. Martin
First Quadrant, L.L.P.
