客户端套接字无法从服务器套接字接收，除非服务器套接字端口是硬编码的

Question

• 我使用默认构造函数创建一个客户端套接字。
• 我通过端口45500向服务器发送数据包。
• 我在服务器端通过端口45500
收到数据包
• 我在服务器端创建一个新套接字
• 我用新的serverSocket发送一个ack。 ack被发送到receivedPacket.getport（）
• 客户端什么也没收到，除非我不在服务器端创建新的套接字，只是发送带有旧套接字的ack（带有硬编码端口45500）
• 我不知道发生了什么事！

客户端

DatagramSocket clientSocket = new DatagramSocket();
byte[] receiveData = new byte[5000];
DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
byte[] connection = connectionRequest.getBytes();
InetAddress IPAdress = InetAddress.getByName("169.xxx.xx.xxx");
DatagramPacket packet = new DatagramPacket(connection, connection.length, IPAdress, 45500);
clientSocket.send(packet);
// doesn't receive unless port #45500 on server side sends!
clientSocket.receive(receivePacket);

服务器

DatagramSocket connectionSocket = new DatagramSocket(45500);
byte[] receiveData = new byte[5000];
DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
connectionSocket.receive(receivePacket);
int clientPort = receivePacket.getPort();
InetAddress IP = receivePacket.getAddress();
byte[] sendData = ("accepted").getBytes();
DatagramSocket serverSocket = new DatagramSocket();
// doesn't work unless connectionSocket (port 45500) sends!
serverSocket.send(new DatagramPacket(sendData, sendData.length, IP, clientPort)); 

Answer 1

双方停用windows10防火墙就行了！