code: public String getHrefResolved() {
          if (Atom10Parser.isAbsoluteURI(href)) {
              return href;
          } else if (baseURI != null && collectionElement != null) {
              final int lastslash = baseURI.lastIndexOf("/");
              return Atom10Parser.resolveURI(baseURI.substring(0, lastslash), collectionElement, href);
          }
          return null;
      }
docs: Get resolved URI of the collection, or null if impossible to determine