Ho fatto questa semplice pagina jsp di test.

codice:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<%@ page pageEncoding="iso-8859-1" %>
<%
Cookie c = new Cookie ("testcookie", "dummy");
response.addCookie (c);

if (request.getParameter ("result") == null)
    response.sendRedirect (request.getRequestURI () + "?result");
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>Test Cookies</title>
<style type="text/css">
<!--
.ok { color: darkgreen; }
.ko { color: red; }
-->
</style>
</head>
<body>

<h1>Test Cookies</h1>
<%
if (request.getParameter ("result") != null)
{
    String msg = "<span class=\"ko\">I cookie non sono accettati</span>";

    Cookie[] cookies = request.getCookies ();

    if (cookies != null)
    {
        for (Cookie cookie : cookies)
        {
            if (cookie.getName ().equals ("testcookie"))
            {
                msg = "<span class=\"ok\">I cookie sono accettati</span>";
                break;
            }
        }
    }

    out.println ("<h3>" + msg + "</h3>");
}
%>


Avvia il test</p>

</body>
</html>