SessionTimeoutFilter.java

/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 *
 * You may not modify, use, reproduce, or distribute this software
 * except in compliance with the terms of the license at:
 * http://developer.sun.com/berkeley_license.html
 */

package filter;

import java.io.IOException;
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.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;


/**
 *
 * @author tgiunipero
 */
@WebFilter(servletNames = {"Controller"})
public class SessionTimeoutFilter implements Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

        HttpServletRequest req = (HttpServletRequest) request;

        HttpSession session = req.getSession(false);

        // if session doesn't exist, forward user to welcome page
        if (session == null) {
            try {
                req.getRequestDispatcher("/index.jsp").forward(request, response);
            } catch (Exception ex) {
                ex.printStackTrace();
            }
            return;
        }

        chain.doFilter(request, response);
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {}

    @Override
    public void destroy() {}

}