/**
     * Validates if the given URL string is a valid URL.
     *
     * @param urlStr the URL string to validate
     * @return true if the URL is valid, false otherwise
     */
    protected boolean isValidUrl(final String urlStr) {
        if (StringUtil.isBlank(urlStr)) {
            return false;
        }
        final String value;
        if (urlStr.startsWith("://")) {
            value = "http" + urlStr;