import crawlercommons.sitemaps.UnknownFormatException; //导入依赖的package包/类
private void startRootElement(String uri, String localName, String qName, Attributes attributes) {
    elementStack.push(localName);

    if ("feed".equals(localName)) {
        delegate = new AtomHandler(url, elementStack, strict);
    }
    // See if it is a RSS feed by looking for the localName "channel"
    // element .
    // This avoids the issue
    // of having the outer tag named <rdf:RDF> that was causing this code to
    // fail. Inside of
    // the <rss> or <rdf> tag is a <channel> tag, so we can use that.
    // See https://github.com/crawler-commons/crawler-commons/issues/87
    // and also RSS 1.0 specification http://web.resource.org/rss/1.0/spec
    else if ("channel".equals(localName)) {
        delegate = new RSSHandler(url, elementStack, strict);
    } else if (isStrictNamespace() && !Namespace.SITEMAP.equals(uri)) {
        setException(new UnknownFormatException("Namespace " + uri + " does not match standard namespace " + Namespace.SITEMAP));
        return;
    } else if ("sitemapindex".equals(localName)) {
        delegate = new XMLIndexHandler(url, elementStack, strict);
    } else if ("urlset".equals(localName)) {
        delegate = new XMLHandler(url, elementStack, strict);
    }
    if (delegate != null) {
        // configure delegate
        delegate.setStrictNamespace(isStrictNamespace());
    }
}
 

import crawlercommons.sitemaps.UnknownFormatException; //导入依赖的package包/类
protected void setException(UnknownFormatException exception) {
    this.exception = exception;
}
 

import crawlercommons.sitemaps.UnknownFormatException; //导入依赖的package包/类
public UnknownFormatException getException() {
    return exception;
}