code: @Override
    public Long getIdPartAsLong() {
      String val = getIdPart();
      if (isBlank(val)) {
        return null;
      }
      return Long.parseLong(val);
    }
docs: Returns the unqualified portion of this ID as a {@link Long}, or
  <code>null</code> if the value is null
  
  @throws NumberFormatException If the value is not a valid Long