class SessionScopeExtractor implements AttributeExtractor {

    @Override
    public Enumeration<String> getKeys() {
        PortletSession session = request.getPortletSession(false);
        if (session != null) {
            return session.getAttributeNames(scope);
        }
        return null;
    }

    public  SessionScopeExtractor(PortletRequest request, int scope);

}