code: public static void appendFooterHeaderStyleXMLToAutomaticStyle(final PageSectionStyle pageSectionStyle,
  																  final Type pageSectionType, final XMLUtil util,
  																  final Appendable appendable) throws IOException {
  		if (pageSectionStyle == null)
  			appendable.append("</style:").append(pageSectionType.getTypeName())
  					.append("-style />");
  		else
  			pageSectionStyle.appendFooterHeaderStyleXMLToAutomaticStyle(util,
  					appendable, pageSectionType);
  	}
docs: Secure version of {@code pageSectionStyle.appendPageSectionStyleXMLToAutomaticStyle}: if the footer (or header) is null,
  then the default type is used.
  
  @param pageSectionStyle the footer or header style, could be null
  @param pageSectionType the type if pageSectionStyle is null.
  @param util an util
  @param appendable the destination
  @throws IOException if an I/O error occurs