Synnefo

/*

 * Copyright 2009 Electronic Business Systems Ltd.

 *

 * This file is part of GSS.

 *

 * GSS is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * GSS is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with GSS.  If not, see <http://www.gnu.org/licenses/>.

 */

package gr.ebs.gss.server;

import java.io.IOException;

import java.util.Date;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

/**

 * A cache filter that properly caches GWT-generated files.

 *

 * @author past

 *

 */

public class CacheFilter implements Filter {

         public void doFilter( ServletRequest request, ServletResponse response,

                         FilterChain filterChain) throws IOException, ServletException {

                 HttpServletRequest httpRequest = (HttpServletRequest)request;

                 String requestURI = httpRequest.getRequestURI();

                 String contextPath = httpRequest.getContextPath();

                if (requestURI.contains(".nocache.")) {

                         HttpServletResponse httpResponse = (HttpServletResponse)response;

                         httpResponse.setHeader("Expires", "Fri, 01 Jan 1990 00:00:00 GMT");

                         httpResponse.setHeader("Pragma", "no-cache");

                         httpResponse.setHeader("Cache-control", "no-cache, must-revalidate");

                 } else if (requestURI.contains(".cache.")) {

                         long today = new Date().getTime();

                         HttpServletResponse httpResponse = (HttpServletResponse)response;

                         httpResponse.setDateHeader("Expires", today+31536000000L);

                 } else if (!requestURI.startsWith(contextPath + "/nonce") &&

                                          !requestURI.startsWith(contextPath + "/token") &&

                                          !requestURI.startsWith(contextPath + "/login") &&

                                          !requestURI.startsWith(contextPath + "/policy")) {

                         long today = new Date().getTime();

                         HttpServletResponse httpResponse = (HttpServletResponse)response;

                         httpResponse.setDateHeader("Expires", today+3456000000L);

                 }

                 filterChain.doFilter(request, response);

         }

        @Override

        public void destroy() {

        }

        @Override

        public void init(FilterConfig filterConfig) {

        }

}