I'm looking over the Jena tutorial, An Introduction to RDF and the Jena RDF API, and am specifically looking at Tutorial01.java. The PersonURI is very vague, as it is defined as:
static String personURI = "http://somewhere/JohnSmith";
Does this URI need to dereferenceable? If so, do all RDF implementation require a web server? Lastly, what is served up at that URI if it does need to be dereferenced and returned?