code: protected void addAppendingAddOnToInputGroup(FacesContext context, ResponseWriter rw,
  			UIComponent appendingAddOnFacet, boolean hasAppendingAddOn, SelectMultiMenu menu) throws IOException {
  		if (hasAppendingAddOn) {
  			if (appendingAddOnFacet.getClass().getName().endsWith("Button") || (appendingAddOnFacet.getChildCount() > 0
  					&& appendingAddOnFacet.getChildren().get(0).getClass().getName().endsWith("Button"))) {
  				rw.startElement("div", menu);
  				rw.writeAttribute("class", "input-group-btn", "class");
  				appendingAddOnFacet.encodeAll(context);
  				rw.endElement("div");
  			} else {
  				rw.startElement("span", menu);
  				rw.writeAttribute("class", "input-group-addon", "class");
  				appendingAddOnFacet.encodeAll(context);
  				rw.endElement("span");
  			}
  		}
  	}
docs: Renders components added seamlessly behind the input field.
  
  @param context
  the FacesContext
  @param rw
  the response writer
  @param appendingAddOnFacet
  optional facet behind the field. Can be null.
  @param hasAppendingAddOn
  optional facet in front of the field. Can be null.
  @throws IOException
  may be thrown by the response writer