(精）必威体育精装版android知识点汇总.docxVIP

Android知识点：一：dom解析，以及写入数据到xml文件：获取输入流：File file = new File(String filepath);InputStream instream = new FileInputStream(file);privatestaticvoid serialize(int data) throws Exception {logs(rewrite xmlFile);// 由android.util.Xml创建一个XmlSerializer实例XmlSerializer serializer = Xml.newSerializer();StringWriter writer = new StringWriter();// 设置输出方向为writerserializer.setOutput(writer);serializer.startDocument(UTF-8, true);serializer.startTag(, datas);serializer.startTag(, data);serializer.text( + data);serializer.endTag(, data);serializer.endTag(, datas);serializer.endDocument();File file = new File(FILE_PATH + FILE_NAME);if (file.exists()) {file.delete();file.createNewFile();}FileOutputStream io = new FileOutputStream(file);String xmlString = writer.toString();io.write(xmlString.getBytes(UTF-8));}//解析输入流，获取输入流中信息privatestaticint parseXmlNative(InputStream is) throws Exception {logs(parseXML in native);String data2 = null; // 获取最终使用期限// 得到Dom解析对象工厂DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();// 通过工厂创建Dom解析对象实例DocumentBuilder db = factory.newDocumentBuilder();// 将xml文件的输入流交给Dom解析对象进行解析，并将Dom树返回Document document = db.parse(is);// 通过Dom树接收到根元素Element rootElement = document.getDocumentElement();NodeList nodeList = rootElement.getElementsByTagName(data);Log.i(TAG, length = + nodeList.getLength());data2 = nodeList.item(0).getFirstChild().getNodeValue();return Integer.parseInt(data2);}二：连接socket并获取返回值try {String sRead;//参数为ip与端口号Socket socket = new Socket(SERVER_IP, PORT);BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));sRead = br.readLine();logs(sRead);socket.close();logs(socket is closed);serialize(Integer.parseInt(sRead));logs(serialize in file, data = + Integer.parseInt(sRead));br.close();} catch (Exception e) {logs(Exception);}三：创建socket服务器publicstaticvoid main(String[] args) {try { ServerSocket ss = new ServerSocket(30000);while (true) { Socket s = ss.accept(); PrintStream ps