无法将任何内容从Python服务器发送到Java clien

Question

我已经建立了一个树莓皮3，我想做一个程序，发送数据时，每当一个按钮被按下我的试验板。我有一个运行在RPi上的Python服务器和一个运行在Windows笔记本上的Java客户机。但是，每当我向Java客户机发送数据时，它都会收到数据，然后由于某种原因，RPi服务器由于“管道中断”而关闭程序。但是这不可能是真的，因为我的Java程序从Pi接收数据！然后，由于Pi服务器关闭，Java程序关闭。但是从我在网上读到的，Python的“error32:breakepipe”是在远程套接字过早关闭时触发的！你知道吗

这是怎么回事？为什么我不能保持我的服务器运行？你知道吗

（PS：我的Java程序接收到的数据是错误的，但它仍然接收到数据。我发送“1\n”，然后接收null。）

以下是我的RPi服务器程序的代码：

import RPi.GPIO as GPIO
from time import sleep
import atexit
import socket
import sys

GPIO.setmode(GPIO.BOARD)
GPIO.setup(5, GPIO.IN)
GPIO.setup(7, GPIO.OUT)


def cleanup():
    print("Goodbye.")
    s.close()
    GPIO.cleanup()
atexit.register(cleanup)

THRESHOLD= 0.3

host= sys.argv[1]
port= 42844

length= 0

def displayDot():
    GPIO.output(7,True)
    sleep(0.2)
    GPIO.output(7,False)
def displayDash():
    GPIO.output(7,True)
    sleep(0.5)
    GPIO.output(7,False)

try:
    print("Initializing connection...")
    s= socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    serverAddress= (host, 42844)
    s.bind(serverAddress)
    print("Connection initialized!")

    print("Waiting for client...")
    s.listen(1) #Puts the server socket into server mode
    client, address= s.accept()
    print(address)
    while True:
        if not GPIO.input(5):
            length+= 0.1
            GPIO.output(7,True)
            s.sendall('1\n')
            print("HELLO??")
        else:
            if length!=0:
                if length>=THRESHOLD:
                    print("Dash") #displayDash()
                else:
                    print("Dot") #displayDot()
                s.sendall('0')
                length= 0
                GPIO.output(7,False)
except KeyboardInterrupt:
    print("\nScript Exited.")
    cleanup();

以下是Java客户端程序的代码：

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

public class MorseClient{
  public static void main(String[] args) throws IOException{
String hostname= null; //Initialize
int portNumber= 0; //Initialize
try {
  hostname= args[0];
  portNumber= Integer.parseInt(args[1]);
}
catch(ArrayIndexOutOfBoundsException aiobe) {
  System.err.println("ERROR. Please specify server address, and port number, respectively");
  System.exit(1);
}

    Socket redoSocket;

    long initTime;

    try(
      Socket echoSocket= new Socket(hostname, portNumber);

      PrintWriter out= new PrintWriter(echoSocket.getOutputStream(), true);

      BufferedReader in= new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));

      BufferedReader stdin= new BufferedReader(new InputStreamReader(System.in));
      ){
        redoSocket= echoSocket;
        System.out.println("Connection made!");

        String userInput= "";

        //Order of priority
        //Connection time= 0
        //Latency= 0
        //Bandwidth= 1
        redoSocket.setPerformancePreferences(0,0,1);

        //Optimizes reliability
        redoSocket.setTrafficClass(0x04);

        echoSocket.setKeepAlive(true);

        String returned= "";
        while(true){
          returned= in.readLine();

          System.out.println(returned);
          if(!(returned.isEmpty())){
            System.out.println(returned);
            System.out.println("YEP");
          }
          System.out.println(returned);
          if(returned==null){
            System.out.println("HAHA");
            System.out.println("Attempting to reconnect...");
            redoSocket= new Socket(hostname,portNumber);
            System.out.println(redoSocket.isConnected());
          }
        }
      }
      catch(Exception e){
        if(e instanceof ConnectException || e instanceof SocketException || e instanceof NullPointerException)
          System.err.println("Connection closed by server");
        else
          System.err.println(e.toString());
      }
  }
}

Pi服务器的输出为：

python ServerMorse.py 192.168.1.101
Initializing connection...
Connection initialized!
Waiting for client...
('192.168.1.14', 58067)
('192.168.1.14', 58067)
Traceback (most recent call last):
  File "ServerMorse.py", in <module>
    s.sendall('1\n')
  File "/usr/lib/python2.7/socket.py", line 228, in meth
    return getattr(self._sock,name)(*args)
socket.error: [Errno 32] Broken pipe
Goodbye.

以及Java客户机的输出：

java MorseClient 192.168.1.101 42844
Connection made!
null
Connection closed by server

Answer 1

上帝啊，你为什么要写一个带插座的服务器？使用烧瓶。你知道吗

http://flask.pocoo.org/

而且，很确定s不应该发送所有的。应该是这样的：

conn, addr = server.accept()
conn.sendall(....     # <- this is what sends

下面是我曾经用套接字编写的服务器的一些示例代码..可能很有用：

def server():
    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM, socket.IPPROTO_TCP)
    address = ('127.0.0.1', 5020)
    server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    server.bind(address)
    server.listen(1)
    conn, addr = server.accept()
    ...
    ...
    conn.sendall(response_ok(some_stuff))
    ...
    conn.close()

（response_ok是我写的一个函数）