// Add defensive null/blank checks
        if (StringUtil.isBlank(username) || StringUtil.isBlank(password)) {
            if (logger.isDebugEnabled()) {
                logger.debug("Login failed: username or password is blank");
            }
            return OptionalEntity.empty();
        }

        if (StringUtil.isBlank(fessConfig.getLdapProviderUrl()) || !validate()) {

        if (StringUtil.isBlank(endpoint)) {
            throw new CrawlingAccessException(
                    "Storage endpoint is blank. Please set the STORAGE_ENDPOINT environment variable or endpoint parameter.");
        }
        builder.endpoint(endpoint);
        final String accessKey = getInitParameter("accessKey", null, String.class);
        if (StringUtil.isBlank(accessKey)) {

     * Returns the default page size if the current size is invalid.
     *
     * @return the validated page size
     */
    public int getPageSize() {
        if (StringUtil.isBlank(size)) {
            return SearchLogPager.DEFAULT_PAGE_SIZE;
        }
        try {
            final int value = Integer.parseInt(size);

     * @param path The FTP path to check.
     * @return true if it matches, false otherwise.
     */
    boolean matches(final String path) {
        if (StringUtil.isBlank(path)) {
            return false;
        }

        try {
            final int pos = path.indexOf('/', 6);
            final URI uri = new URI(pos == -1 ? path : path.substring(0, pos));

     * @return the corresponding file type, or the default value if not found
     */
    public String get(final String mimetype) {
        final String filetype = mimetypeMap.get(mimetype);
        if (StringUtil.isBlank(filetype)) {
            return defaultValue;
        }
        return filetype;
    }

    /**
     * Gets the default file type value used when MIME type is not found.
     *

     * @return the virtual host key, or empty string if blank or null
     */
    protected String getHostKey(final RelatedQuery entity) {
        final String key = entity.getVirtualHost();
        return StringUtil.isBlank(key) ? StringUtil.EMPTY : key;
    }

    /**
     * Retrieves related queries for a given search term.
     * The search is performed using the current virtual host context and

        final UrlQueue<?> urlQueue = CrawlingParameterUtil.getUrlQueue();
        if (urlQueue == null) {
            return;
        }

        final String url = urlQueue.getUrl();
        if (StringUtil.isBlank(url) || url.startsWith("file:")) {
            // not target
            return;
        }

        try {
            final URI uri = new URI(url);
            final String host = uri.getHost();

            return "Unknown error";
        }

        final Supplier<String> stacktraceString = () -> {
            final StringBuilder sb = new StringBuilder();
            if (StringUtil.isBlank(cause.getMessage())) {
                sb.append(cause.getClass().getName());
            } else {
                sb.append(cause.getMessage());
            }

                    continue;
                }

                final boolean isDirectory = blobName.endsWith("/");
                final String name = getName(blobName);

                if (StringUtil.isBlank(name)) {
                    continue;
                }

                final ZonedDateTime lastModified =

     *
     * @param str
     *            the string to check
     * @return {@literal true} if the string is not blank
     * @see #isBlank(String)
     */
    public static boolean isNotBlank(final String str) {
        return !isBlank(str);
    }

    /**
     * Returns true if the string contains the specified character.
     *
     * @param str
     *            the string to check