What would the differences be in implementing remote business logic?
Currently we are planning on using ADF to develop front-end web applications (moving from Struts). What are the differences between the front end calling EJBs using TopLink vs ADF Business Components through RMI in terms of scalability as the migration from Struts to ADF will also encompass PL/SQL and Oracle Forms, thus increasing the user count drastically?
ADF is pretty broad, as it encompasses front end all the way down through data access. It’s a great RAD framework if you are going to use the entire stack, but isn’t so hot if you are only going to use one portion or the other.
I am assuming you are talking about using either TopLink or ADF business components (BC4J) for the data access layer.
I would say that if you are planning on using an RMI based application, that TopLink would probably be better, mainly because the power of BC4J is in its view objects, which don’t serialize (hence translating those results into TopLink style value objects, anyway).
If you are doing a straight up and down web application and don’t really care about EJBs and RMI then I think you’ll find that BC4J offers a lot in the way of making standard web applications scale… Long story short, it maps SQL into view objects, which are basically smart datagrids that have very tunable behavior, which can be bound directly to JSF components of the Oracle ADF Faces, giving really good seamless RAD.