docs: @Override
      protected boolean hasChildren(final String relative) throws IOException {
          ZipFile zip = createZipFile();
          if (null == zip) {
              return false;
          }
          Enumeration<? extends ZipEntry> entries = zip.entries();
          while (entries.hasMoreElements()) {
              ZipEntry entry = entries.nextElement();
              if ((relative.equals("")) || entry.getName().startsWith(relative + File.separator)) {
                  return true;
              }
          }
  
          zip.close();
          return false;
      }