服务器如何知道客户端的端口号，在该端口号中它将使用java编程套接字将响应发送到客户端？

import java.io.*;
import java.net.*;

public class Server {
    public static void main(String[] args) {
        try {
            // 创建ServerSocket对象并监听指定端口
            ServerSocket serverSocket = new ServerSocket(8080);
            
            // 接受客户端连接请求
            Socket clientSocket = serverSocket.accept();
            
            // 获取客户端的IP地址和端口号
            InetAddress clientAddress = clientSocket.getInetAddress();
            int clientPort = clientSocket.getPort();
            
            System.out.println("客户端IP地址: " + clientAddress.getHostAddress());
            System.out.println("客户端端口号: " + clientPort);
            
            // 创建输入流和输出流
            BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
            PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
            
            // 读取客户端发送的请求信息
            String request = in.readLine();
            
            // 处理请求并生成响应
            String response = "Hello, Client!";
            
            // 将响应发送到客户端
            out.println(response);
            
            // 关闭连接
            clientSocket.close();
            serverSocket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}