HelloWorld.java

    @GET
    @Path("provenance/hello/{name}")
    @Produces("text/provenance-notation")
    public String helloProvenance(@PathParam("name") String name,
            @Context UriInfo ui) throws IOException {
        // Get our absolute URI
        // See http://cxf.apache.org/docs/jax-rs-basics.html#JAX-RSBasics-URIcalculationusingUriInfoandUriBuilder        
        UriBuilder appUri = ui.getBaseUriBuilder();
        // Absolute URIs for resources we are to give provenance about
        URI helloURI = appUri.path(getClass(), "hello").build(name);        
        
        // Prepare prefixes for PROV-N qualified names
        URI appURI = appUri.build("").resolve("../");        
        URI helloPrefix = helloURI.resolve("./");
        
        // The PROV-N qualified name for our /hello/{name} resource
        String helloEntity = "hello:" + helloPrefix.relativize(helloURI);
        
        // Simple PROV-N trace, see <http://www.w3.org/TR/prov-n/>
        // Here this is done in a naive way by loading a template 
        // from src/main/resources and do string-replace to insert
        // our URIs.
        String template = IOUtils.toString(getClass().getResourceAsStream("/provTemplate.txt"));
        String prov = MessageFormat.format(template, 
                helloPrefix, appURI, helloEntity, name);
        // Note: PROV-N should be be built using say the PROV Toolbox 
        // rather than this naive template approach!
        return prov;
    }
}