code: public void setOnKeyDown(String onkeydown)
      {
          AbstractHtmlState tsh = getState();
          tsh.registerAttribute(AbstractHtmlState.ATTR_JAVASCRIPT, ONKEYDOWN, onkeydown);
      }
docs: Sets the onKeyDown javascript event.
  @param onkeydown the onKeyDown event.
  @jsptagref.attributedescription The onKeyDown JavaScript event.
  @jsptagref.databindable false
  @jsptagref.attributesyntaxvalue <i>string_onKeyDown</i>
  @netui:attribute required="false" rtexprvalue="true"
  description="The onKeyDown JavaScript event."