code: public void setLang(String lang)
      {
          _spanState.registerAttribute(AbstractHtmlState.ATTR_GENERAL, HtmlConstants.LANG, lang);
      }
docs: Sets the lang attribute for the HTML span.
  @param lang
  @jsptagref.attributedescription The lang for the HTML span.
  @jsptagref.attributesyntaxvalue <i>string_lang</i>
  @netui:attribute required="false" rtexprvalue="true"
  description="The lang for the HTML span"