To delete cookie from servlet, get the cookie from the request object and use setMaxAge(0) and then add the cookie to the response object. To delete cookie from JSP, use the following scriptlet: <% Cookie killMyCookie = new Cookie("mycookie", null); killMyCookie.setMaxAge(0); killMyCookie.setPath("/"); response.addCookie(killMyCookie); %>

You can set the cookie by setValue() method on cookie object. Example : cookie.setValue("My own value");

You can pass information to a JSP page from the servlet. Using setAttribut() on request object in the servlet and forward it as follows : RequestDispatcher rd = getServletContext().getRequestDispatcher("test.jsp"); rd.forward(request,response);

You can pass information from JSP to the included JSP using the <jsp:param> in the body of <jsp:include> action. Example : <jsp:include page="relativeURL"> <jsp:param name="parameterName" value="parameterValue"/> </jsp:include>

A hidden comment is a JSP comment that is not sent to the client. Syntax : <%-- Hidden comment --%>

ServletContext and ServletConfig are declared in the deployment descriptor. ServletConfig is one per servlet and can be accessed only within that specific servlet. ServletContext is one per web application and accessible to all the servlet in the web application.

JSP Actions are XML tags that are executed at run time. These tags transfer the control between the pages and also use the server side beans : Some JSP Actions are : * jsp:include, * jsp:useBean, * jsp:setProperty, * jsp:getProperty, * jsp:forward, * jsp:plugin.

The <jsp:useBean> may also optionally have a body. You can make use of a JSP expression within the <jsp:setProperty> action in the body of <jsp:useBean>. For Example : <jsp:useBean id="foo" class="Bar.Foo" > <jsp:setProperty name="foo" property="today" value="<%=java.text.DateFormat.getDateInstance().format(new java.util.Date()) %>" / > </jsp:useBean >

Under JSP 1.0, the "page" implicit object page is equivalent to "this", and returns a reference to the servlet generated by the JSP page.

By setting HTTP header attributes you can prevent the output of my JSP or Servlet pages from being cached by the browser. You can do this by the following code : <% 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 %>