code: public void setUsemap(String usemap) {
          _imageState.registerAttribute(AbstractHtmlState.ATTR_GENERAL, HtmlConstants.USEMAP, usemap);
      }
docs: Sets the client-side image map declaration for the HTML iage tag.
  
  @param usemap the map declaration.
  @jsptagref.attributedescription The client-side image map declaration for the HTML image tag.
  @jsptagref.attributesyntaxvalue <i>string_useMap</i>
  @netui:attribute required="false" rtexprvalue="true"
  description="The client-side image map declaration for the HTML image tag."