/**
     * Displays the login page.
     *
     * @return the HTML response for the login page
     */
    @Execute
    public HtmlResponse index() {
        getSession().ifPresent(session -> session.removeAttribute(INVALID_OLD_PASSWORD));
        return asIndexPage(null).useForm(LoginForm.class);
    }

    private HtmlResponse asIndexPage(final LoginForm form) {
        if (form != null) {
            form.clearSecurityInfo();

            if (session != null) {
                final String sesState = (String) session.getAttribute(OIC_STATE);
                if (StringUtil.isNotBlank(sesState)) {
                    session.removeAttribute(OIC_STATE);
                    final String code = request.getParameter("code");
                    final String reqState = request.getParameter("state");
                    if (logger.isDebugEnabled()) {

            if (session != null) {
                final String sesState = (String) session.getAttribute(SAML_STATE);
                if (StringUtil.isNotBlank(sesState)) {
                    session.removeAttribute(SAML_STATE);
                    try {
                        final Auth auth = new Auth(getSettings(), request, response);
                        auth.processResponse();

        final Attribute attr = new BasicAttribute(name, value);
        final ModificationItem mod = new ModificationItem(DirContext.REMOVE_ATTRIBUTE, attr);
        modifyList.add(mod);
    }

    /**
     * Modifies an entry.
     *
     * @param dn The DN of the entry.
     * @param modifyList The list of modification items.