final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final PrimaryCipher cipher = ComponentUtil.getPrimaryCipher();
        userCode = cipher.encrypt(userCode);
        if (fessConfig.isValidUserCode(userCode)) {
            return userCode;
        }
        return null;
    }

    /**
     * Deletes the user code cookie from the client browser.

    }

    String getUserCodePattern();

    Integer getUserCodeMinLengthAsInteger();

    Integer getUserCodeMaxLengthAsInteger();

    default boolean isValidUserCode(final String userCode) {
        if (userCode == null) {
            return false;
        }

        final int length = userCode.length();