ServerSocket serverSocket = new ServerSocket(6666); //綁定端口號為6666的端口

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;
/**
 * 服務端
 * @author Administrator
*
*/
public class Server {
	public static void main(String[] args) {
		ServerSocket server = null;
		Socket socket = null;
		try {
			//準備服務器端用的通訊對象（套接字）,指明端口號為8888
			server = new ServerSocket(8888);
			//到指定端口去阻塞監(jiān)聽,一旦有客戶端請求發(fā)送過來，那么立即自動與客戶端建立連接
			socket = server.accept();
			System.out.println("服務器端準備ok");
			//我要發(fā)送到客戶端的內容
			String msg = "你好,我是服務器，這是我的第一次通訊,請問你收到了嗎";
			OutputStream os = socket.getOutputStream();//準備輸出對象
			BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(os));
			bw.write(msg);
			bw.newLine();
			bw.flush();
			//接收客戶端發(fā)送的信息
			InputStream is = socket.getInputStream();
			BufferedReader br = new BufferedReader(new InputStreamReader(is));
			String reply = br.readLine();
			System.out.println("我是服務器，接收到信息："+reply);
			br.close();
			is.close();
			bw.close();
			os.close();
			socket.close();
			server.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.Socket;
import java.net.UnknownHostException;
/**
 * 客戶端
 * @author Administrator
*
*/
public class Client {
	public static void main(String[] args) {
		Socket socket = null;
		try {
			socket = new Socket("localhost", 8888);
			System.out.println("客戶端準備完成");
			//客戶端開始接受請求
			InputStream is = socket.getInputStream();
			BufferedReader br = new BufferedReader(new InputStreamReader(is));
			String msg = br.readLine();
			System.out.println("我是客戶端，接收到信息："+msg);
			//客戶端接收到服務器端的信息之后，需要反饋信息給服務器
       	 //客戶端想要反饋給服務器端的信息 
			String reply = "我是客戶端，收到你的信息，這是我的反饋";
			OutputStream os = socket.getOutputStream();//準備客戶端的輸出流
			BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(os));
			bw.write(reply);
			bw.newLine();
			bw.flush();
			bw.close();
			os.close();
			br.close();
			is.close();
			socket.close();
		} catch (UnknownHostException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}