public class Client {
    public static void main(String[] args) throws IOException {
        //TCP協(xié)議，發(fā)送數(shù)據(jù)
        //1.創(chuàng)建Socket對(duì)象
        //細(xì)節(jié)：在創(chuàng)建對(duì)象的同時(shí)會(huì)連接服務(wù)端
        //      如果連接不上，代碼會(huì)報(bào)錯(cuò)
        Socket socket = new Socket("127.0.0.1",10000);
        //2.可以從連接通道中獲取輸出流
        OutputStream os = socket.getOutputStream();
        //寫出數(shù)據(jù)
        os.write("aaa".getBytes());
        //3.釋放資源
        os.close();
        socket.close();
    }
}

public class Server {
    public static void main(String[] args) throws IOException {
        //TCP協(xié)議，接收數(shù)據(jù)
        //1.創(chuàng)建對(duì)象ServerSocker
        ServerSocket ss = new ServerSocket(10000);
        //2.監(jiān)聽客戶端的鏈接
        Socket socket = ss.accept();
        //3.從連接通道中獲取輸入流讀取數(shù)據(jù)
        InputStream is = socket.getInputStream();
        int b;
        while ((b = is.read()) != -1){
            System.out.println((char) b);
        }
        //4.釋放資源
        socket.close();
        ss.close();
    }
}

package com.utils;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
/**
 * @BelongsProject: CSDN_score
 * @BelongsPackage: com.utils
 * @Author:qiutianshuo
 * @Description:
 * @CreateTime: 2023-09-01 11:24
 * @Version: 1.0
 */
public class SendDemo {
    public static void main(String[] args) throws IOException {
        //創(chuàng)建發(fā)送端的Socket對(duì)象(DatagramSocket)
        // DatagramSocket() 構(gòu)造數(shù)據(jù)報(bào)套接字并將其綁定到本地主機(jī)上的任何可用端口
        DatagramSocket ds = new DatagramSocket();
        //創(chuàng)建數(shù)據(jù)，并把數(shù)據(jù)打包
        //DatagramPacket(byte[] buf, int length, InetAddress address, int port)
        //構(gòu)造一個(gè)數(shù)據(jù)包，發(fā)送長(zhǎng)度為 length的數(shù)據(jù)包到指定主機(jī)上的指定端口號(hào)。
        byte[] bys = "hello,udp,我來了".getBytes();
        DatagramPacket dp = new DatagramPacket(bys,bys.length, InetAddress.getByName("127.0.0.1"),10086);
        //調(diào)用DatagramSocket對(duì)象的方法發(fā)送數(shù)據(jù)
        //void send(DatagramPacket p) 從此套接字發(fā)送數(shù)據(jù)報(bào)包
        ds.send(dp);
        //關(guān)閉發(fā)送端
        //void close() 關(guān)閉此數(shù)據(jù)報(bào)套接字
        ds.close();
    }
}

package com.utils;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
public class ReceiveMessageDemo {
    public static void main(String[] args) throws IOException {
        //接收數(shù)據(jù)
        //1.創(chuàng)建DatagramSocket對(duì)象（快遞公司）
        //細(xì)節(jié)：
        //在接收的時(shí)候，一定要綁定端口
        //而且綁定的端口一定要跟發(fā)送的端口保持一致
        DatagramSocket ds = new DatagramSocket(10086);
        //2.接收數(shù)據(jù)包
        byte[] bytes = new byte[1024];
        DatagramPacket dp = new DatagramPacket(bytes,bytes.length);
        //該方法是阻塞的
        //程序執(zhí)行到這一步的時(shí)候，會(huì)在這里死等
        //等發(fā)送端發(fā)送消息
        System.out.println(11111);
        ds.receive(dp);
        System.out.println(2222);
        //3.解析數(shù)據(jù)包
        byte[] data = dp.getData();
        int len = dp.getLength();
        InetAddress address = dp.getAddress();
        int port = dp.getPort();
        System.out.println("接收到數(shù)據(jù)" + new String(data,0,len));
        System.out.println("該數(shù)據(jù)是從" + address + "這臺(tái)電腦中的" + port + "這個(gè)端口發(fā)出的");
        //4.釋放資源
        ds.close();
    }
}