java获得rss订阅中的信息

public class Jdom {public static void main(String[] args){try{URL url = new URL("http://www.google.com/ig/api?hl=zh_cn&weather=tianjin");InputStream instr = url.openStream();String s,str;BufferedReader in = new BufferedReader(new InputStreamReader(instr));StringBuffer sb = new StringBuffer();Writer out =new BufferedWriter(new OutputStreamWriter(new FileOutputStream("weater.txt"),"utf-8"));while((s=in.readLine())!=null){sb.append(s);}str = new String(sb);out.write(str);out.close();in.close();}catch(Exception e){e.printStackTrace();}File f = new File("weater.txt");//暂存的文件DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();String str = null;try{DocumentBuilder builder = factory.newDocumentBuilder();Document doc = builder.parse(f);NodeList nl = (NodeList)doc.getElementsByTagName("forecast_conditions");//需要的节点的tagnameNodeList n2 = nl.item(0).getChildNodes();str = n2.item(4).getAttributes().item(0).getNodeValue()+","+n2.item(1).getAttributes().item(0).getNodeValue()+"°C";System.out.println(str);}catch(Exception e){}}}