TwistedPython服务器和Java聊天

我在raywenderlich.com上找到了这篇精彩的教程：

它创建了一个Twisted Python服务器，并与应用程序iphone聊天，我会让服务器也与Java聊天，现在我编写一些代码，这是Python服务器：

from twisted.internet.protocol import Protocol, Factory
from twisted.internet import reactor


class IphoneChat(Protocol):
def connectionMade(self):
    #self.transport.write("""connected""")
    self.factory.clients.append(self)
    print "clients are ", self.factory.clients

def connectionLost(self, reason):
    self.factory.clients.remove(self)

def dataReceived(self, data):
    #print "data is ", data
    a = data.split(':')
    if len(a) > 1:
        command = a[0]
        content = a[1]

        msg = ""
        if command == "iam":
            self.name = content
            msg = self.name + " has joined"

        elif command == "msg":
            msg = self.name + ": " + content

        print msg

        for c in self.factory.clients:
            c.message(msg)

def message(self, message):
    self.transport.write(message + '\n')


factory = Factory()
factory.protocol = IphoneChat
factory.clients = []

reactor.listenTCP(1025, factory)
print "Chat server started"
reactor.run()

然后我创建了一个简单的java示例来连接到服务器：

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

public class MyClassSocket  {

private ObjectInputStream sInput;       // to read from the socket
private ObjectOutputStream sOutput;     // to write on the socket
private Socket socket;

private String server, username;
private int port;

MyClassSocket(String server, int port, String username) {
    this.server = server;
    this.port = port;
    this.username = username;
}

private void display(String msg) {

    System.out.println(msg);      // println in console mode

}

public boolean start() {

    try {
        socket = new Socket(server, port);
    }
    // if it failed not much I can so
    catch(Exception ec) {
        display("Error connectiong to server:" + ec);
        return false;
    }

    String msg = "Connection accepted " + socket.getInetAddress() + ":" + socket.getPort();
    display(msg);

    try
    {

        sInput  = new ObjectInputStream(socket.getInputStream()); //<-------- block here
        sOutput = new ObjectOutputStream(socket.getOutputStream());
    }
    catch (IOException eIO) {
        display("Exception creating new Input/output Streams: " + eIO);
        return false;
    }

    return true;

}

public static void main(String[] args) {

    MyClassSocket client = new MyClassSocket("localhost",1025,"PieroJava");
    client.start();
}

}

---

怎么办？

我建议不要使用ObjectInputStream和ObjectOutputStream。无论如何，要让它们与Python服务器进行良好的交互可能是一个挑战，而且它们并没有实现一个非常好的协议。我建议使用更简单的协议，并提供更好的跨语言支持，例如

---

在任何情况下，

newobjectinputstream

似乎都会被阻塞，直到它可以从连接中读取字节为止。如果您想让它成功，您基于Twisted的服务器将需要将Java对象流的开头写入连接。

您如何知道客户机阻塞的那一行？我在那一行的前面和后面放了一些System.out.println，并且只打印第一行……异常情况如何？您确定会报告异常吗？从这听上去，getInputStream不会因为任何原因而被阻塞，所以你观察到它被阻塞是很奇怪的。问题是，我没有异常，停留在那里，不去看，我发现了类似的问题：这似乎是我的问题，在评论回答中，发现问题的用户谈话，但是他有一个java服务器…啊。该问题涉及ObjectInputStream构造函数从输入流读取。但您的服务器在安装时不会向连接写入任何内容。因此，客户端无需读取任何内容，因此读取将永远阻塞。

sInput  = new ObjectInputStream(socket.getInputStream());