我有一個讀取 RSS 提要的簡單代碼。它曾經在給定的 RSS 提要上工作正常，但由于某種原因停止工作，出現以下異常：Exception in thread "main" java.lang.IllegalArgumentException: Invalid documentat com.rometools.rome.io.WireFeedInput.build(WireFeedInput.java:312)at com.rometools.rome.io.WireFeedInput.build(WireFeedInput.java:234)at com.rometools.rome.io.SyndFeedInput.build(SyndFeedInput.java:150)這是代碼：    URL url  = new URL("http://www.dpreview.com/feeds/reviews/latest");    XmlReader reader = null;    try {        reader = new XmlReader(url);        SyndFeed feeder = new SyndFeedInput().build(reader);        System.out.println("Feed Title: "+ feeder.getAuthor());        for (Iterator i = feeder.getEntries().iterator(); i.hasNext();) {            SyndEntry syndEntry = (SyndEntry) i.next();            System.out.println(syndEntry.getTitle());        }    } finally {        if (reader != null)            reader.close();    }有什么我想念的嗎？