code: void appendXMLHelper(final XMLUtil util, final Appendable appendable, final String numberStyleName, final CharSequence number) throws IOException {
  		this.numberStyle.appendXMLHelper(util, appendable, numberStyleName, number);
  	}
docs: A helper to create the XML representation of the float style
  @param util a util
  @param appendable the destination
  @param numberStyleName the style name ("currency-style", ...)
  @param number the number itslef
  @throws IOException if an I/O error occurs