SessionAuthentication.java

package edu.ub.gpr.statistics.filters;

import java.io.IOException;
import java.util.Properties;
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 org.apache.log4j.PropertyConfigurator;

/**
 *
 * @author oriol.lopez
 */
public class SessionAuthentication implements Filter
{

    private static String authType;

    Logger log = Logger.getLogger(SessionAuthentication.class);

    public void init(FilterConfig filterConfig) throws ServletException
    {
        try
        {
            Properties config = new Properties();
            config.load(this.getClass().getClassLoader().getResourceAsStream("gprstats.properties"));

            PropertyConfigurator.configure(config);

            authType = config.getProperty("gprstats.authentication");

            log.debug("SessionAuthentication Filter has been initialized.");
        }
        catch ( Exception ex )
        {
            log.error("Error " + ex.getMessage(), ex);
        }
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException
    {
        HttpServletRequest _request = (HttpServletRequest)request;
        HttpServletResponse _response = (HttpServletResponse)response;

        log.debug("New request filtered: " + _request.getRequestURI());

        if ( _request.getRequestURI().equals("/gprstats/login.jsp") || 
                _request.getRequestURI().equals("/gprstats/login") ||
                _request.getRequestURI().equals("/gprstats/logout") ||
                _request.getRequestURI().equals("/gprstats/guest.jsp") )
        {
            chain.doFilter(request, response);
        }
        else
        {
            if ( authType.equals("NONE") )
            {
                chain.doFilter(request, response);
            }
            else if ( authType.equals("SIMPLE") )
            {
                HttpSession session = _request.getSession();
                String logged = (String)session.getAttribute("logged");

                if ( logged == null )
                {
                    _response.sendRedirect("/gprstats/login.jsp");
                }
                else
                {
                    chain.doFilter(request, response);
                }
            }
            else if ( authType.equals("AUTENUB") )
            {
                throw new UnsupportedOperationException("Not supported yet.");
            }
        }
    }

    public void destroy()
    {
        log.info("SessionAuthentication Filter will be destroyed.");
    }

}