}

    /**
     * Gets the list of alternate links associated with this URL.
     * @return the list of alternate links, or an empty list if none
     */
    public List<SitemapAlternateLink> getAlternateLinks() {
        if (alternateLinks == null) {
            alternateLinks = new ArrayList<>();
        }
        return alternateLinks;
    }

    /**
     * Adds an alternate link to this sitemap URL.

        assertEquals(3, sitemapUrl.getAlternateLinks().size());

        final SitemapAlternateLink link1 = sitemapUrl.getAlternateLinks().get(0);
        assertEquals("en", link1.getHreflang());
        assertEquals("http://www.example.com/en/page.html", link1.getHref());

        final SitemapAlternateLink link2 = sitemapUrl.getAlternateLinks().get(1);
        assertEquals("ja", link2.getHreflang());