8.3

【目录】

URL

UDP

枚举

解析

URL
类 URL 代表一个统一资源定位符，它是指向互联网“资源”的指针。
主要方法摘要：

Java代码：

public class Work01 {
    public static void main(String[] args) {
    /*下面是对一张图片进行解析，然后保存在文件中*/
        try {
            URL url = new URL("http://p0.so.qhimg.com/t012094b2ef46b76685.jpg");
            File file = new File("d://12.jpg"); 
            if(!file.exists()){
                file.createNewFile();
            }
            OutputStream os = new FileOutputStream(file);
            InputStream is =url.openStream();
            byte[] array = new byte[1024];
            int i = is.read(array);
            while(i!= -1){
                os.write(array, 0, i);
                i = is.read(array);
            }
            os.flush();
            os.close();
            is.close();

        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        /*下面是360网页的解析*/
        try {
            URL url = new URL("http://hao.360.cn/");
            InputStream is = url.openStream();
            BufferedReader br = new BufferedReader(new InputStreamReader(is));
            String line = br.readLine();
            while (line != null) {
                System.out.println(line);
                line = br.readLine();
            }
            br.close();
            is.close();
        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

UDP

public class Send {
    public static void main(String[] args) {
        try {
            DatagramSocket send = new DatagramSocket();
            DatagramSocket receiver = new DatagramSocket(8088);
            byte[] receiverArray = new byte[1024];
            Scanner scanner = new Scanner(System.in);
            while (true) {
                System.out.println("我输入：");
                String s = scanner.next();
                byte[] array = s.getBytes();
                DatagramPacket packet = new DatagramPacket(array, array.length, InetAddress.getByName("192.168.0.66"),
                        8080);
                System.out.println("发送端发送：" + s);
                send.send(packet);

                DatagramPacket packetre = new DatagramPacket(receiverArray, 1024);
                receiver.receive(packetre);
                byte[] data = packetre.getData();
                System.out.println("发送端收到:" + new String(data, 0, packetre.getLength()));
            }
        } catch (SocketException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}

public class Receiver {
    public static void main(String[] args) {
        try {
            DatagramSocket re = new DatagramSocket(8080);
            DatagramSocket send = new DatagramSocket();
            byte[] array = new byte[1024];
            Scanner scanner = new Scanner(System.in);
            while (true) {
                DatagramPacket packet = new DatagramPacket(array, 1024);
                re.receive(packet);
                byte[] data = packet.getData();
                System.out.println("接收端收到:" + new String(data, 0, packet.getLength()));

                String sendString = scanner.next();
                System.out.println("接收端发送：" + sendString);
                byte[] sendByte = sendString.getBytes();
                DatagramPacket packetSend = new DatagramPacket(sendByte, sendByte.length,
                        InetAddress.getByName("192.168.0.66"), 8088);
                send.send(packetSend);

            }
            // re.close();
        } catch (SocketException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

枚举

java代码

JSON解析

package com.day07.sax;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

public class JSONTest {
             /* 对写的内容解析*/
    public static void main(String[] args) {
         String json = creatJSON();
         JSONObject obj = JSONObject.fromObject(json);
         System.out.println(obj.getString("city"));
         JSONObject today = obj.getJSONObject("today");
         JSONArray array = today.getJSONArray("index");
         for (int i = 0; i <array.size(); i++) {
            JSONObject obj1 = array.getJSONObject(i);
            System.out.println(obj1.getString("name"));
        }

    }
            /*编入内容*/
    private static String creatJSON(){
        JSONObject obj = new JSONObject();
        obj.put("city", "北京");
        obj.put("cityid", "123");
        JSONObject today = new JSONObject();
        today.put("date", "2015-8-03");
        today.put("week", "周一");
        JSONArray array = new JSONArray();
        JSONObject index1 = new JSONObject();
        index1.put("name", "感冒");
        JSONObject index2 = new JSONObject();
        index2.put("name", "防晒");
        JSONObject index3 = new JSONObject();
        index3.put("name", "炎热");
        array.add(index1);
        array.add(index2);
        array.add(index3);
        today.put("index", array);
        obj.put("today", today);
        System.out.println(obj.toString());
        return obj.toString();

    }
}
/*运行结果：{"city":"北京","cityid":"123","today":{"date":"2015-8-03","week":"周一","index":[{"name":"感冒"},{"name":"防晒"},{"name":"炎热"}]}}
北京
感冒
防晒
炎热*/

XML解析

DOM解析

SAX解析