Sessao hibernate

public class HibernateSessionFilter implements Filter {  
  
    /** 
     * Logger. 
     */  
    private static Log log = LogFactory.getLog("HibernateSessionFilter");  
  
    public static final String SESSION_KEY = "hibernateSession";  
  
    public static final String CONNECTION_KEY = "hibernateConnection";  
  
    private static final SessionFactory sessionFactory;
    
    static {
	    sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
	}
    
    public void doFilter(ServletRequest req,  
            ServletResponse res, FilterChain filterChain)  
            throws ServletException, IOException {      	  
  
        /* 
         * Retrieve the session or instantiate it. 
         */  
    	
    	HttpServletRequest request = (HttpServletRequest) req;
    	HttpServletResponse response = (HttpServletResponse) res;
    	
        // nunca uma sessao é pega na linha abaixo
        Session session = (Session) request.getAttribute(SESSION_KEY);  
        Connection connection = (Connection) request  
                .getAttribute(CONNECTION_KEY);  
        if (session == null) {          	
        	
            session = sessionFactory.openSession() ;  
            request.setAttribute(SESSION_KEY, session);          
            
            System.out.println("########################### ABRIU");
            
        } else {  
          	        	
        	System.out.println("########################### ABERTA");
        	
            connection = (Connection) request.getAttribute(CONNECTION_KEY);  
            try {  
                session.reconnect(connection);  
            } catch (RuntimeException e) {  
                log.info("Already connected");  
                log.info(e);  
            }  
        }  
  
        try {  
            filterChain.doFilter(request, response);  
        }  
  
        finally {  
  
            try {  
                connection = session.disconnect();  
                request.setAttribute(CONNECTION_KEY, connection);  
                
                Statistics stats = sessionFactory.getStatistics();
                stats.setStatisticsEnabled(true);
                stats.logSummary();
                
            } catch (RuntimeException ex) {  
                log.error("Unexpected exception on closing Hibernate Session", ex);  
            }  
        }  
    }

	public void destroy() {
		// TODO Auto-generated method stub
		
	}

	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub
		
	}