<% request.setAttribute("decorator", "none"); response.setHeader("Cache-Control","no-cache"); //HTTP 1.1 response.setHeader("Pragma","no-cache"); //HTTP 1.0 response.setDateHeader ("Expires", 0); //prevents caching at the proxy server %>

More on JSP tags

Struts 2 provides many more tags which you can learn about here

You can keep playing with the JSP console or Start OGNL Interactive Demo