網絡編程

#

DNS：Domain Name System，域名系統

客戶端代碼

package com.ibeifeng2;

import java.io.IOException;
import java.io.OutputStream;
import java.net.Socket;
import java.net.UnknownHostException;

public class ClientDemo {
    public static void main(String[] args) {
        try {
            test();
        } catch (UnknownHostException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    private static void test() throws UnknownHostException, IOException {
        // 1 創建客戶端的 socket對象
        Socket socket = new Socket("localhost", 12345); 

        // 2 獲取寫入流對象
        OutputStream fos = socket.getOutputStream();
        fos.write("你吃飯了嗎".getBytes());

        // 關閉資源
        fos.close();
        socket.close();
    }
}

服務器端

package com.ibeifeng2;

import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;

//網絡通信，  --->ip ,---->端口    （前1024不要使用）
public class ServerDemo {
    public static void main(String[] args) {
        try {
            test();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    public static void test() throws IOException {
        //1 服務端的socket對象
        ServerSocket server = new ServerSocket(12345);
        System.out.println("服務器啓動");

        //2 監聽12345端口，接受客戶端的連接
        Socket socket =  server.accept();//阻塞
        //3 建立客戶端的寫入通道
        InputStream is  = socket.getInputStream();
        byte[] byts = new byte[1024];
        is.read(byts);
        System.out.println(new String(byts));

        //4 關閉資源
        socket.close();

    }
}

---