code: public String resolveRelativeUri(String uri) {
          // sometimes we get uri's massaged from File(String), so check for
          // a root directory separator char
          if (uri.startsWith("/") || uri.startsWith(File.separator)) {
              return uri;
          } else {
              return baseURI + uri;
          }
      }
docs: Get the full value of a URI relative to this compilations context
  uses current file as the base.
  @param uri The relative URI
  @return absolute URI