JavaSE socket 基于UDP Server/Client的实现

上一篇演示了一个简单的基于TCP/IP  双向的控制台聊天程序,

本篇基于Java的UDP实现类

DatagramSocket / DatagramPacket

展示下如何用这两个类完成一个简单的通信。由于时间仓促，读和写两个并发线程的编写并没有调试成功，欢迎完成的小伙伴留言 附上代码 或者 讲出为什么像示例这样做不行的原因，灰常感谢。

Server 端

package com.test.socket;import java.net.DatagramPacket;import java.net.DatagramSocket;import java.net.InetAddress;import java.net.InetSocketAddress;import java.util.Scanner;/** * Created by szh on 2017/9/12. */public class UDPSocketServer extends Thread {    public static DatagramSocket datagramSocket = null;    public static InetAddress senderAddr = null;    public static int senderPort = -1;    static {        try {            datagramSocket = new DatagramSocket(new InetSocketAddress(InetAddress.getByAddress(new byte[]{127, 0, 0, 1}), 8080));        } catch (Exception e) {            e.printStackTrace();        }    }    @Override    public void run() {        try {            while (true) {                byte[] buffer = new byte[8192];                DatagramPacket packet = new DatagramPacket(buffer, 8192);                datagramSocket.receive(packet);                String msg = new String(packet.getData());                senderAddr = packet.getAddress();                senderPort = packet.getPort();                System.out.println("Sender :\n  addr -> " + senderAddr + "\n  port -> " + senderPort + "\nMsg : " + msg);            }        } catch (Exception e) {            e.printStackTrace();        } finally {            datagramSocket.close();        }    }    public static void main(String[] args) {        try {            //将Server 绑定在本地的127.0.0.1 8080端口            DatagramSocket datagramSocket = new DatagramSocket(new InetSocketAddress(InetAddress.getByAddress(new byte[]{127, 0, 0, 1}), 41002));//            //创建一个读取客户端发送消息的进程 并启动//            new UDPSocketServer().start();////            Scanner scanner = new Scanner(System.in);//            String line = null;//            while (!(line = scanner.nextLine()).equals("exit")) {//                if (senderPort != -1 && senderAddr != null) {//                    byte[] byteMsg = line.getBytes();//                    datagramSocket.send(new DatagramPacket(byteMsg, 0, byteMsg.length, senderAddr, senderPort));//                }//            }            while (true) {                byte[] buffer = new byte[8192];                DatagramPacket packet = new DatagramPacket(buffer, 8192);                datagramSocket.receive(packet);                String msg = new String(packet.getData());                senderAddr = packet.getAddress();                senderPort = packet.getPort();                System.out.println("Sender :\n  addr -> " + senderAddr + "\n  -> port " + senderPort + "\nMsg : " + msg);            }        } catch (Exception e) {            e.printStackTrace();        } finally {            datagramSocket.close();        }    }}

Client 端

package com.test.socket;import java.net.DatagramPacket;import java.net.DatagramSocket;import java.net.InetAddress;import java.util.Scanner;/** * Created by szh on 2017/9/12. */public class UDPSocketClient {    public static InetAddress serverAddr = null;    public static int serverPort = -1;    static {        try {            serverAddr = InetAddress.getByAddress(new byte[]{127, 0, 0, 1});            serverPort = 41002;        } catch (Exception e) {            e.printStackTrace();        }    }    public static void main(String[] args) {        DatagramSocket datagramSocket = null;        try {            datagramSocket = new DatagramSocket(42000+ (int)Math.floor(Math.random()*1000));            Scanner scanner = new Scanner(System.in);            String line = null;            while (!(line = scanner.nextLine()).equals("exit")) {                byte[] byteMsg = line.getBytes();                if (serverPort != -1 && serverAddr != null){                    DatagramPacket sendPacket = new DatagramPacket(new byte[0], 0, serverAddr, serverPort);                    sendPacket.setData(byteMsg);                    System.out.println("发送消息");                    datagramSocket.send(sendPacket);                }            }        } catch (Exception e) {            e.printStackTrace();        } finally {            datagramSocket.close();        }    }}

测试截图：

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