Server Class

import java.io.*;
import java.net.*;
import java.util.Date;

public class Server {

	private ServerSocket serverSocket;
	private Socket clientEnd;

	private int port;

	public Server(int port) {

		this.setPort(port);

		Thread server = new Thread(() -> {
			try {
				Runtime.getRuntime().addShutdownHook(new Thread(){public void run(){
				    try {
				        serverSocket.close();
				        System.out.println("The server is shut down!");
				    } catch (IOException e) { /* failed */ }
				}});
				serverSocket = new ServerSocket(port);
				serverSocket.setReuseAddress(true);

				clientEnd = serverSocket.accept();

				try (DataInputStream dataIn = new DataInputStream(clientEnd.getInputStream());
						DataOutputStream dataOut = new DataOutputStream(clientEnd.getOutputStream());) {

					while (true) {

						String message = dataIn.readUTF();
						if (message.matches("[Ee]xit"))
							break;
						message = "on " + new Date() + " , the Server Received " + message;

						dataOut.writeUTF(message);
						dataOut.flush();


					}

				}

			} catch (IOException e) {

				e.printStackTrace();
			}
			finally {
				try {
					serverSocket.close();
				} catch (IOException e) {

					e.printStackTrace();
				}
			}
		});
		server.start();

	}

	public int getPort() {
		return port;
	}

	public void setPort(int port) {
		this.port = port;
	}

	public static void main(String[] args) throws IOException {


		Server server = new Server(8020);
		Client local = new Client("localhost", 8020);

	}

}