记得上一次接触socket这一块还是在大三抓耳挠腮的整毕设的时候，两年后的今天又用到了它，那就把Socket实现组播什么的做一个记录吧。

TcpServer

public class TcpServer {private static boolean isruning = true;public static void main(String[] args) {try {ServerSocket serverSocket = new ServerSocket(5583);while (isruning) {// 连接Socket socket = serverSocket.accept();System.out.println("有新客户端（" + socket.getInetAddress() + "）连接。。");OutputStream stream = socket.getOutputStream();OutputStreamWriter writer = new OutputStreamWriter(stream);writer.write("hello socket!");writer.flush();writer.close();System.out.println("客户端（" + socket.getInetAddress() + "）会话结束。。");}serverSocket.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}
}

TcpClient

public class TcpClient {public static void main(String[] args) {String host = "localhost"; // 要连接的服务端IP地址int port = 5583; // 要连接的服务端对应的监听端口try {// 与服务端建立连接Socket client = new Socket(host, port);InputStream inputStream = client.getInputStream();InputStreamReader reader = new InputStreamReader(inputStream);BufferedReader bufferedReader = new BufferedReader(reader);String message = bufferedReader.readLine();System.out.println(message);bufferedReader.close();client.close();} catch (UnknownHostException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}}

UdpSend

public class UdpSend {public static void main(String[] args) {MulticastSocket socket;try {socket = new MulticastSocket(8842);socket.setTimeToLive(1);InetAddress address = InetAddress.getByName("233.0.0.0");socket.joinGroup(address);byte[] buf = "hello world!".getBytes();DatagramPacket p = new DatagramPacket(buf, buf.length, address,8842);socket.send(p);System.out.println("广播已经发出");} catch (IOException e) {e.printStackTrace();}}
}

UdpReceive

public class UdpReceive {public static void main(String[] args) {MulticastSocket socket;try {socket = new MulticastSocket(8842);socket.setTimeToLive(1);InetAddress address = InetAddress.getByName("233.0.0.0");socket.joinGroup(address);byte[] buf = new byte[3000];DatagramPacket p = new DatagramPacket(buf, buf.length);socket.receive(p);System.out.println("接受到" + p.getAddress() + "的广播消息"+ new String(p.getData()));} catch (IOException e) {e.printStackTrace();}}
}

2019年1月4日16:43:00 更新 ----------------------------------

后来实现的，比上个版本更好一点 贴上来

public class cfg {public static String ip = "192.168.0.106";public static int port = 8030;
}

import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;public class Client {public static void main(String[] args) {try {// 与服务端建立连接Socket client = new Socket(cfg.ip, cfg.port);System.out.println("连接成功！");new Send(client).start();new Recerver(client).start();//socket.close();} catch (UnknownHostException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}
}

import com.sun.xml.internal.messaging.saaj.util.ByteInputStream;import java.io.*;
import java.net.Socket;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;public class Recerver extends Thread {Socket socket;public Recerver(Socket client) {this.socket = client;}@Overridepublic void run() {super.run();InputStream inputStream = null;try {inputStream = socket.getInputStream();for (; ; ) {DataInputStream stream = new DataInputStream(inputStream);int head = -1;while ((head = stream.read()) != 0xff) {System.out.print("bad data");}System.out.print("head:" + head);int len = stream.readInt();byte[] data = new byte[len];stream.read(data, 0, len);String str = new String(data, Charset.forName("utf-8"));System.out.println(socket.getInetAddress() + ":" + str);}} catch (IOException e) {System.out.println(socket.getInetAddress() + " 已经断开");}}
}

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.Socket;
import java.nio.ByteBuffer;
import java.util.Scanner;public class Send extends Thread {Socket socket;public Send(Socket socket) {this.socket = socket;}@Overridepublic void run() {super.run();try {OutputStream out = socket.getOutputStream();Scanner scanner = new Scanner(System.in);for (; ; ) {String msg = scanner.nextLine();byte[] content = msg.getBytes("utf-8");ByteBuffer byteBuffer = ByteBuffer.allocate(content.length + 5);byteBuffer.put((byte) 0xff);byteBuffer.putInt(content.length);byteBuffer.put(content);out.write(byteBuffer.array());out.flush();}} catch (IOException e) {e.printStackTrace();}}
}

import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;public class Server {public static void main(String[] args) {try {ServerSocket serverSocket = new ServerSocket(cfg.port);System.out.println("服务启动：" + InetAddress.getLocalHost().getHostAddress() + ":" + serverSocket.getLocalPort());for (; ; ) {// 连接Socket socket = serverSocket.accept();System.out.println("有新客户端（" + socket.getInetAddress() + "）连接");new Send(socket).start();new Recerver(socket).start();}//serverSocket.close();} catch (IOException e) {System.out.print("服务端异常:" + e.getMessage());}}
}