To preface I am new to web development. I am looking at creating a core set of RESTful web services around a valuable document library of sorts (initial CRUD abilities). In doing so I am theoretically creating a perfectly re-usable and scalable back-end to be used by unanticipated applications in the future.
My question centers around the best practice for doing this. My initial requirement has me also creating a unique front end. Would I make the front end and back end completely separate projects to enhance the re-usability. It would increase overhead.
Looking at using GWT, Restlet, and the Java EE technology stack if this influences the setup at all.
Most important is design a clean Java API - independent of REST, RMI, or whatever protocol you want to use. From a clean Java API, you can support any access method.
Unless you have a use case for these other access methods, don't build them now. You can build it when you need it.
The easiest interface to add initially is a web based interface where your web app runs in the same JVM as your core API. I'd do this if this works for your use case. Building a separate console application that accesses your core API via a REST (or whatever) protocol is a lot more work..