* <li>If the data at the supplied path exists, the Future returns an Optional object
* containing the data.</li>
* <li>If the data at the supplied path does not exist, the Future returns
- * Optional#absent().</li>
+ * Optional.empty().</li>
* <li>If the read of the data fails, the Future will fail with a
* {@link ReadFailedException} or an exception derived from ReadFailedException.</li>
* </ul>