Android -空对象引用，正在解析RSS文件

try {
    XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
    factory.setNamespaceAware(true);
    XmlPullParser parser = factory.newPullParser();
} catch (XmlPullParserException e) {
    e.printStackTrace();
}

try {
    XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
    factory.setNamespaceAware(true);
    XmlPullParser parser = factory.newPullParser();
    parser.setInput(new InputStreamReader(inputStream));

    int eventType = parser.getEventType();
    while (eventType != XmlPullParser.END_DOCUMENT) {
        String tagName = parser.getName();
        switch (eventType) {
            case XmlPullParser.START_TAG:
                if ("item".equals(tagName)) {
                    // 解析item标签内的内容
                } else if ("title".equals(tagName)) {
                    // 解析title标签内的内容
                } else if ("link".equals(tagName)) {
                    // 解析link标签内的内容
                }
                break;
            case XmlPullParser.END_TAG:
                break;
        }
        eventType = parser.next();
    }
} catch (XmlPullParserException | IOException e) {
    e.printStackTrace();
}

import com.rometools.rome.feed.synd.SyndFeed;
import com.rometools.rome.io.SyndFeedInput;
import com.rometools.rome.io.XmlReader;

URL feedUrl = new URL("https://example.com/rss.xml");
XmlReader reader = new XmlReader(feedUrl);
SyndFeed feed = new SyndFeedInput().build(reader);