Although very similar applications sitemap generator and URL checker are different in that while sitemap generator does 'crawling' or 'spidering' (that is scan trough all pages of a site on same domain) Url checker examines any list of URLs and doesn't crawl (doesn't add new links which are found on pages,only examines given list of urls).
So it can't generate sitemaps but you can download Sitemap Generator from here: