Question

我正在尝试用Java创建可以与python客户端通信的套接字服务器。我遇到了一个问题，如果我启动服务器，通过python发送一条消息，然后立即退出，那么一切运行正常，但是如果客户端发送一条消息，然后再次侦听套接字，服务器将不会响应。

public class PrimeServer {

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

        int portNumber = 4444;

        try (
                ServerSocket serverSocket = new ServerSocket(portNumber);
                Socket clientSocket = serverSocket.accept();
                PrintWriter out =
                        new PrintWriter(clientSocket.getOutputStream(), true);
                BufferedReader in = new BufferedReader(
                        new InputStreamReader(clientSocket.getInputStream()))
        ) {

            String inputLine;
            String outputLine;
            String rawMessage;

            // Initiate conversation with client
            PrimeProtocol ppc = new PrimeProtocol();
            outputLine = String.format("%1022s", "Ready").replace(' ', '0');
            out.println(outputLine);
            System.out.println("Over while");
            while ((inputLine = in.readLine()) != null) {
                System.out.println("In while");
                if (ppc.processInput(Integer.parseInt(inputLine))){
                    rawMessage = "True";
                } else {
                    rawMessage = "False";
                }
                outputLine = String.format("%1024s", rawMessage).replace(' ', '0');
                System.out.println("Outputting " + rawMessage);
                out.println(outputLine);

            }
            System.out.println("Passed while.");
        } catch (IOException e) {
            System.out.println("Exception caught when trying to listen on port "
                    + portNumber + " or listening for a connection");
            System.out.println(e.getMessage());
        }
    }
}

还有很好的python代码：

msg_len = 1024
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("127.0.0.1", 4444))
init_message = sock.recv(msg_len).decode("UTF-8")
init_message = init_message.replace('0', '')
print(init_message)
print(len(init_message))
sock.send(b'3')

使用此代码，java服务器的输出为：

Over while
In while
Outputting True
Passed while.

客户端输出为：

1024
Ready

连接断开后。

但是，如果我将此行添加到客户端：new_message = sock.recv(msg_len).decode("UTF-8") 制作新的python：

msg_len = 1024
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("127.0.0.1", 4444))
init_message = sock.recv(msg_len).decode("UTF-8")
print(len(init_message))
init_message = init_message.replace('0', '')
print(init_message)

sock.send(b'3')

new_message = sock.recv(msg_len).decode("UTF-8")

服务器阻塞，输出仅为：

Over while

客户端输出时：

1024
Ready

同时也干扰。

有什么想法吗？

Answer 1

原来是需要冲洗的python套接字。新的python代码：

msg_len = 1024
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("127.0.0.1", 4444))
init_message = sock.recv(msg_len).decode("UTF-8")
print(len(init_message))
init_message = init_message.replace('0', '')
print(init_message)

sock.send(b'3\n')

new_message = sock.recv(msg_len).decode("UTF-8")
print(new_message)

（在发送的邮件中添加了\ n）。

Java Socket Server与Python客户端的通信，程序不会进入“ inputLine = in.readLine（）”循环

1 个答案: