I'm not sure but as I understood she deal with distributed files  and she want to create a web app  on the server as a proxy to access them by using metadata's.

So there are two things that should be considered:



1- the way you use to generate metadata's

2- access method



The first one is more important but it's completely depends on second. But the second is your question and for this, the simplest way, as someone else mentioned is using of this format: \\machinName\dirName\fileName .when those files are shared (by enough permission) but this approach is completely platform dependent and it lacks many things. But this is enough for your project J

Don't worry about "war" or "ear" because just dynamic resource (such as Servlets) must be placed under your web app root and the web server itself handles the rest.