Java中的BindException简单客户端服务器应用程序

Question

我正在尝试用Java创建一个简单的应用程序以将消息发送到服务器。当我运行该应用程序时，虽然没有使用端口4344的进程（我尝试更改端口号，但始终会抛出异常），但服务器上出现BindException（地址已在使用中）。尽管如此，该消息仍会到达服务器并显示该消息。

服务器代码：

import java.io.DataInputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.TimeUnit;

import javax.swing.JOptionPane;

public class Server implements Runnable {

    public static void main(String[] args){
        Server s = new Server();
        s.run();        
    }

    public Server() {
        Thread serverThread = new Thread(this);
        serverThread.start();
    }

    @Override
    public void run() {
        try {
            ServerSocket serverSocket = new ServerSocket(4344);
            while(true) {
                Socket clientSocket = serverSocket.accept();

                DataInputStream inputSocket = new DataInputStream(clientSocket.getInputStream());
                System.out.println(inputSocket.readUTF());
                inputSocket.close();
                clientSocket.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}

客户代码：

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

import javax.swing.JOptionPane;

public class Client {
    Socket serverConnection;
    String serverIp = "192.168.182.1";

    public static void main(String[] args){    
        Client c = new Client();            
    }

    public Client() {
        sendMessage("message");
    }

    public void sendMessage(String msg) {
        try {
            serverConnection = new Socket(serverIp, 4344);
            DataOutputStream dataOutput = new DataOutputStream(serverConnection.getOutputStream());
            dataOutput.writeUTF(msg);
            dataOutput.close();
            serverConnection.close();
        } catch (IOException e) {
            e.printStackTrace();
        }   
    }

}