Question

I have an application where both the backend and the frontend are built in Java. The backend provides some functionalities like accessing the DB, etc. While the frontend built in Struts calls those functions.

I’m looking for a way to make any Java class easily callable on TCP, ideally in my mind this could be done by extending a specific class, let’s say:

public class MyClass extends ThisIsAnAPI

making in this way all the public functions callable on a network protocol.

With such a framework the frontend could be easily implemented in other languages, like Ruby (On Rails), by making network requests to the backend APIs written in Java and exposed on TCP.

Any tips?

Answer 1

If you are likely to go to a JavaScript/Ajax UI then I would take the time to expose the backend as RESTful services. Using JAX/RS this is a matter of a few lines of a code and some annotations and an interface.

If you are staying pure Java, it’s pretty trivial these days to turn a POJO into a remotely callable EJB: just a couple of annotations.

It may sound like overkill, but in terms of effort and cost (given a free app server such as WebSphere CE or JBoss) it’s not that big a deal. However if you don’t go for EJBs then you need to look at two big issues:

1. Security. You’ve got some TCP-callable services. How sensitive are those services? Do they need authentication and authorisation? You can all too easily open up sensitive databases to the whole company or even the internet.
2. Resilience and Scaling. How will you manage failure scenarios? EJBs exposed via RMI/IIOP can be clusterd and hence you can scale and deal with errors. If you start with a technology capable of doing that, even if you don’t need the functionality right now, you are well placed for the future.