package Day10;

import java.net.DatagramPacket;

import java.net.DatagramSocket;

import java.net.InetSocketAddress;

import java.util.Scanner;

/**

 * 聊天消息接受者

 * @author Administrator

 *

 */

class Receiver implements Runnable {

    public void run() {

        DatagramSocket ds = null;

        try {

            /**

             * 创建接收端

             * 1、DatagramSocket(int port)

             *             构造一个数据报套接字绑定到本地主机上的指定端口。

             */

            ds = new DatagramSocket(12345);

            while(true) {

                // 接收数据包

                byte[] data = new byte[1024];

                DatagramPacket dp = new DatagramPacket(data, data.length);

                ds.receive(dp);

                // 获取接收到的数据包的信息

                /**

                 * 1、InetAddress类型     getAddress()

                 *                    返回机器的IP地址的数据报发送或者接收的数据报。 (数据报二进制)

                 * 2、getHostAddress()

                 *               返回的IP地址字符串的文本表示。

                 *

                 */

                String msg = new String(data, 0, dp.getLength());

                String ip = dp.getAddress().getHostAddress();

                //int port = dp.getPort();

                System.err.println(ip + msg);

            }

        }catch(Exception e) {

            e.getStackTrace();

        }finally {

            // 关闭套接字

            if(ds != null)

                ds.close();

        }

    }

}

/**

 * 聊天消息发送者

 * @author Administrator

 *

 */

class Sender implements Runnable{

    Scanner s = null;

    DatagramSocket ds = null;

    @Override

    public void run() {

        try {

            // 创建发送端

            ds = new DatagramSocket();

            // 设置端口和ip

            int port = 12345;

            String ip = "172.180.8.50";

            // 创建控制台扫描器

            s = new Scanner(System.in);

            while(true) {

                // 读取控制台信息

                // System.out.println("--------没有格式，直接输入--------");

                String str = "cjj: "+ s.nextLine();

                byte[] msg = str.getBytes();

                /**

                 * 发送数据

                 * 1、InetSocketAddress(InetAddress addr, int port)

                 *                    创建一个套接字地址的IP地址和端口号。

                 * 2、 getSocketAddress()

                 *                 得到了SocketAddress(通常是IP地址+端口号)都的远程主机,这包被发送到或来自。

                 * 3、send(DatagramPacket p)

                 *               从这个套接字发送一个数据报包。

                 */

                DatagramPacket dp = new DatagramPacket(msg, msg.length);

                dp.setSocketAddress(new InetSocketAddress(ip , port));

                ds.send(dp);

            }

        }catch(Exception e) {

            e.getStackTrace();

        }finally {

            if(ds != null)

                ds.close();

            if(s != null)

                s.close();

        }

    }

}

public class QQ {

    public static void main(String[] args) throws Exception {

        new Thread(new Sender()).start();

        new Thread(new Receiver()).start();

    }

}

package QQ;

import java.io.IOException;

import java.net.DatagramPacket;

import java.net.DatagramSocket;

import java.net.InetSocketAddress;

import java.net.SocketException;

import java.util.Scanner;

public class QQ1 {

    public static void main(String[] args) {

        new Thread(new Sender()).start();

        new Thread(new Receiver()).start();

    }

}

class Sender implements Runnable {

    @Override

    public void run() {

        Scanner sc = new Scanner(System.in);

        DatagramSocket ds = null;

        try {

            ds = new DatagramSocket();

            while (true) {

                System.out.print("请输入发送的内容 ：");

                String str = sc.nextLine();

                DatagramPacket dp = new DatagramPacket(str.getBytes(), str.getBytes().length);

                dp.setSocketAddress(new InetSocketAddress("172.180.8.50", 12345));

                ds.send(dp);

                System.out.println();

            }

        } catch (SocketException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        } finally {

            if (ds != null)

                ds.close();

            if (sc != null)

                sc.close();

        }

    }

}

class Receiver implements Runnable {

    @Override

    public void run() {

        DatagramSocket ds = null;

        try {

            ds = new DatagramSocket(12345);

            while (true) {

                byte[] data = new byte[1024];

                DatagramPacket dp = new DatagramPacket(data, data.length);

                ds.receive(dp);

                String str = new String(data, 0, dp.getLength());

                String ip = dp.getAddress().getHostAddress();

                int port = dp.getPort();

                System.err.println("老刘：" + str);

            }

        } catch (SocketException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        } finally {

            if (ds != null) {

                ds.close();

            }

        }

    }

}