Java网络编程TCP/IP,UDP

TCP/IP

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客户端

package com.cxx.netty;
import java.io.*;
import java.net.Socket;
/**
 * @Author: cxx
 * 客户端
 * @Date: 2018/5/27 14:14
 */
public class GreetingClient {
    private static String host="127.0.0.1";
    private static int port = 9999;

    public static void main(String[] args) throws InterruptedException {
        for (int i=0;i<100;i++){
            start(i);
        }
    }

    public static void start(int i){
        try{
            Socket client = new Socket(host,port);
            print(client);
            OutputStream outputStream = client.getOutputStream();
            DataOutput dout = new DataOutputStream(outputStream);
            dout.writeUTF(i+":hello server");
            InputStream inputStream = client.getInputStream();
            DataInput din = new DataInputStream(inputStream);
            System.out.println("服务器响应:"+din.readUTF());
            System.out.println();
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    public static void print(Socket client){
        System.out.println("远程主机ip:"+client.getRemoteSocketAddress());
    }
}

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服务端

package com.cxx.netty;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * @Author: cxx
 * 服务端
 * @Date: 2018/5/27 14:17
 */
public class GreetingServer extends Thread {
    private static int port=9999;
    private static boolean flag=true;
    public static void main(String[] args){
        Thread t = new GreetingServer();
        t.run();
    }

    @Override
    public void run() {
        try {
            System.out.println("开启服务端..等待连接：");
            ServerSocket client = new ServerSocket(port);
            // client.setSoTimeout(10000);
            while (flag){
                Socket server = client.accept();
                DataInput din = new DataInputStream(server.getInputStream());
                System.out.println("server:"+din.readUTF());
                DataOutput dou = new DataOutputStream(server.getOutputStream());
                dou.writeUTF("谢谢你连接我！");
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

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运行结果

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UDP构建一个简单的聊天室

package com.cxx.netty;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;

/**
 * @Author: cxx
 * UDP实现一个聊天程序
 * @Date: 2018/5/27 15:14
 */
public class UdpChat {
    public static void main(String[] args) throws Exception {
        DatagramSocket sendSocket = new DatagramSocket();
        DatagramSocket receiveSocket = new DatagramSocket(44444);
        new Thread(new Send(sendSocket)).start();
        new Thread(new Receive(receiveSocket)).start();

    }
}

//定义发送线程任务
class Send implements Runnable{
    private DatagramSocket socket;
    public Send(DatagramSocket socket){
        this.socket = socket;
    }

    @Override
    public void run() {
        //一直发送数据
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String line = null;
        try{
            System.out.println("聊天室开启：");
            while ((line=br.readLine())!=null){
                byte[] data = line.getBytes();
                DatagramPacket packet = new DatagramPacket(data,data.length, InetAddress.getByName("127.0.0.1"), 44444);
                socket.send(packet);
                if (line.equals("baibai")){
                    break;
                }
            }
            br.close();
            socket.close();
        }catch (Exception e){
            e.printStackTrace();
        }

    }
}

//定义接收线程任务
class Receive implements Runnable{
    private DatagramSocket socket;
    public Receive(DatagramSocket socket){
        this.socket=socket;
    }

    @Override
    public void run() {
        //一直接收数据
        while (true) {
            try {
                byte[] data = new byte[1024];
                DatagramPacket packet = new DatagramPacket(data, data.length);
                socket.receive(packet);
                String line = new String(packet.getData(), 0, packet.getLength());
                String ip = packet.getAddress().getHostAddress();
                if (line.equals("baibai")) {
                    System.out.println(ip + "==离开了聊天室!");
                }
                System.out.println(ip + "说：" + line);

            } catch (Exception e) {
                e.printStackTrace();
            }
        }

    }
}

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