服務端程式：

package doc_02_tcp.server;

import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * 模組說明： 伺服器端程式
 * 
 */
public class TimeServer {
    public static void main(String[] args) {
        try
 
 {
            // 列印本機ip地址
            InetAddress address = InetAddress.getLocalHost();
            System.out.println(address);
            // 建立一個serversocket，監聽客戶端請求
            ServerSocket ss = new ServerSocket(9999);
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
            // 採用迴圈不斷接受來自客戶端的請求
 

            while (true) {
                Socket socket = ss.accept();
                PrintWriter out = new PrintWriter(socket.getOutputStream());
                out.println(sdf.format(new Date()));
                out.flush();
                out.close();
                socket.close();
            }
        } catch
 
 (Exception e) {
            e.printStackTrace();
        }
    }
}

客戶端程式：

package doc_02_tcp.client;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;

/**
 * 模組說明： 客戶端程式
 * 
 */
public class TimeClient {
    public static void main(String[] args) {
        try {
            String localhost = String.valueOf(InetAddress.getLocalHost()).split("/")[1];
            Socket socket = new Socket(localhost, 9999);
            BufferedReader input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            String currentTime = input.readLine();
            System.out.println("current time from server：" + currentTime);
            input.close();
            socket.close();
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}