Top Most Implement Filter in Java

/*
 * Created on Jan 29, 2010
 *
 */
package com.filter;

import java.io.IOException;
import java.util.TimeZone;

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;
import javax.servlet.http.HttpSession;

import org.apache.log4j.Logger;

import com.common.Constants;

public class SecurityFilter implements Filter{

    private static Logger log = Logger.getLogger(SecurityFilter.class);
    public static final String BROWSER_REQUEST_URL = "__BROWSER_REQUEST_URL";
    public static final String BROWSER_REQUEST_QUERY = "__BROWSER_REQUEST_QUERY";
   
    public SecurityFilter() {
        super();
    }

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        long millis = System.currentTimeMillis();
        log.debug("SecurityFilter.doFilter() entry -------------------------------");
        log.debug( "ServletResponse runtime class: " + response.getClass().getName());
        try {
            HttpServletRequest r = (HttpServletRequest)request;
            HttpServletResponse res = (HttpServletResponse)response;
            HttpSession session = r.getSession(false);
           
            if((session == null || session.getAttribute(Constants.CURRENT_USER) == null)&& (!r.getRequestURI().equals(r.getContextPath() + "/")
            && !r.getRequestURI().equals(r.getContextPath() + "/index.jsp")
            && !r.getRequestURI().equals(r.getContextPath() + "/login.action")
            && !r.getRequestURI().equals(r.getContextPath() + "/logout.action")
             && !r.getRequestURI().equals(r.getContextPath() + "/selectedDonationSite.action")
            && !r.getRequestURI().equals(r.getContextPath() + "/retiveUserPassword.action")
            && !r.getRequestURI().equals(r.getContextPath() + "/retiveUserPassword.action")
            && !r.getRequestURI().equals(r.getContextPath() + "/feedback.action")
            && !r.getRequestURI().equals(r.getContextPath() + "/userRegistrationAction.action")
            )){
            res.sendRedirect(r.getContextPath() + "/index.jsp");
            }else{
            //TimeZone savedZone = TimeZone.getDefault();
            //TimeZone tz = TimeZone.getTimeZone("GMT");
                //TimeZone.setDefault(tz);
            chain.doFilter(request, response);
            //TimeZone.setDefault(savedZone);
            }
        } catch(Exception e){
        e.printStackTrace();
        }finally {
            log.debug("SecurityFilter.doFilter() exit -------------------------------");
        }
    }

    public void destroy() {
    }

public void init(FilterConfig fc) throws ServletException {
}

public static String getUrl(ServletRequest r ) {
   return (String)r.getAttribute( BROWSER_REQUEST_URL );
}

public static String getQueryString(ServletRequest r ) {
   return (String)r.getAttribute( BROWSER_REQUEST_QUERY );
}
}