/**
     * Returns the OSDD document.
     *
     * @return the OSDD document as a stream response
     */
    @Execute
    public ActionResponse index() {
        if (isLoginRequired()) {
            return redirectToLogin();
        }
        return osddHelper.asStream();
    }

     */
    @Execute
    public ActionResponse index(final ThumbnailForm form) {
        validate(form, messages -> {}, () -> asHtml(virtualHost(path_Error_ErrorJsp)));
        if (isLoginRequired()) {
            return redirectToLogin();
        }

        final Map<String, Object> doc =
                searchHelper.getDocumentByDocId(form.docId, queryFieldConfig.getResponseFields(), getUserBean()).orElse(null);

    /**
     * The index page.
     * @return The HTML response for the index page.
     */
    @Execute
    public HtmlResponse index() {
        if (isLoginRequired()) {
            return redirectToLogin();
        }

        return asHtml(virtualHost(path_IndexJsp)).useForm(SearchForm.class, op -> {
            op.setup(form -> {
                buildFormParams(form);

    /**
     * The advance search page.
     * @param form The search form.
     * @return The HTML response.
     */
    @Execute
    public HtmlResponse advance(final SearchForm form) {
        if (isLoginRequired()) {
            return redirectToLogin();
        }
        validate(form, messages -> {}, () -> asHtml(virtualHost(path_IndexJsp)).renderWith(data -> {
            buildInitParams();

     */
    @Execute
    public ActionResponse index(final CacheForm form) {
        validate(form, messages -> {}, () -> asHtml(virtualHost(path_Error_ErrorJsp)));
        if (isLoginRequired()) {
            return redirectToLogin();
        }

        Map<String, Object> doc = null;
        try {

     *
     * @return HtmlResponse containing the rendered help page or redirect to login if authentication is required
     */
    @Execute
    public HtmlResponse index() {
        if (isLoginRequired()) {
            return redirectToLogin();
        }

        return asHtml(virtualHost(path_HelpJsp)).useForm(SearchForm.class, op -> {
            op.setup(form -> {
                buildFormParams(form);

     */
    @Execute
    public ActionResponse index(final GoForm form) throws IOException {
        validate(form, messages -> {}, () -> asHtml(virtualHost(path_Error_ErrorJsp)));
        if (isLoginRequired()) {
            return redirectToLogin();
        }

        Map<String, Object> doc = null;
        try {
            doc = searchHelper

     * and user authentication status.
     *
     * @return true if login is required, false otherwise
     */
    protected boolean isLoginRequired() {
        if (fessConfig.isLoginRequired() && !fessLoginAssist.getSavedUserBean().isPresent()) {
            return true;
        }
        return false;
    }

    /**

     * @param form the form to populate with configuration values
     */
    public static void updateForm(final FessConfig fessConfig, final EditForm form) {
        form.loginRequired = fessConfig.isLoginRequired() ? Constants.TRUE : Constants.FALSE;
        form.resultCollapsed = fessConfig.isResultCollapsed() ? Constants.TRUE : Constants.FALSE;
        form.loginLink = fessConfig.isLoginLinkEnabled() ? Constants.TRUE : Constants.FALSE;

    }

    default void setLoginRequired(final boolean value) {
        setSystemPropertyAsBoolean(Constants.LOGIN_REQUIRED_PROPERTY, value);
    }

    default boolean isLoginRequired() {
        return getSystemPropertyAsBoolean(Constants.LOGIN_REQUIRED_PROPERTY, false);
    }

    default void setResultCollapsed(final boolean value) {