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copied!<p>It might at that point be <em>too late</em> to change the response headers. They will simply be ignored. You can verify the presence of response headers in a HTTP debugger tool like <a href="http://getfirebug.com" rel="nofollow noreferrer">Firebug</a>.</p> <hr> <p><img src="https://i.stack.imgur.com/NVqah.png" alt="alt text"></p> <hr> <p>In the JSP, you need to ensure that they are set <em>before</em> the response is committed (i.e. all headers are already sent; you cannot send another headers afterwards). I.e. ensure that they are in the very top of the JSP file and that no template text is before that piece of <em>scriptlet</em>. Template text may cause a commit of the response. The normal practice, however, is to use a <code>Filter</code> for this. </p> <p>Implement <a href="http://download.oracle.com/javaee/6/api/javax/servlet/Filter.html" rel="nofollow noreferrer"><code>javax.servlet.Filter</code></a> wherein <code>doFilter()</code> method look like follows:</p> <pre><code>HttpServletResponse httpResponse = (HttpServletResponse) response; httpResponse.setHeader("Cache-Control", "no-cache", "no-store", "must-revalidate"); // HTTP 1.1 httpResponse.setHeader("Pragma", "no-cache"); // HTTP 1.0 httpResponse.setDateHeader("Expires", 0); // Proxies. chain.doFilter(request, response); </code></pre> <p>Map this in <code>web.xml</code> on an <code>url-pattern</code> of <code>*.jsp</code> and it ought to work.</p> <h3>See also:</h3> <ul> <li><a href="https://stackoverflow.com/questions/49547/making-sure-a-web-page-is-not-cached-across-all-browsers">Making sure a webpage is not cached, across all browsers</a></li> </ul>

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