code: public static URI appendPath(URI base, String path) throws URISyntaxException {
      return new URI(base.getScheme(), base.getAuthority(),
          PathUtils.concatPath(base.getPath(), path), base.getQuery(), base.getFragment());
    }
docs: Appends the given path to the given base URI.
  
  @param base the base URI
  @param path the path to append
  @return the URI resulting from appending the base and the path
  @throws URISyntaxException if URI syntax error is encountered