2

我正在尝试“编写两个实现 FTP 服务器的 Java 程序，分别响应 USER 和 PASS，每个客户端线程和线程池。” 我只是想在上交之前确保一切都井井有条。这是我的源代码。我遇到的唯一麻烦是弄清楚如何处理“FTPProtocol 客户端”；我应该在拥有 thread.start 后将其销毁吗？

FTPServer.java

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;


 public class FTPserver
{   
public static void main(String [] args)
{
    if (args.length != 1) 
        throw new IllegalArgumentException( "Parameter(s): <Port>");

    int threadPoolSize = 10;
    int port = Integer.parseInt(args[0]); 

    final ServerSocket server;
    try 
    {
        server = new ServerSocket(port);
    } 
    catch (IOException e1) 
    {
        return;
    }

    for (int i = 0; i < threadPoolSize; i++) 
    {
        Thread thread = new Thread() 
        {
            public void run() 
            {
                while (true) 
                {
                    try 
                    {
                        Socket sock = server.accept();
                        FTPProtocol client = new FTPProtocol(sock);
                    } 
                    catch (IOException e)
                    {
                        System.err.println(e.getMessage());
                        return;
                    }
                }
            }
        };
        thread.start();
    }
}
}

FTP协议.java

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;

class FTPProtocol implements Runnable
{
static String greeting = "220 Service Ready.\r\n";
static String needPassword = "331 User name ok, need password.\r\n";
static String closing = "421 Service not available, closing control connection.\r\n";
static byte[] reply220 = null;
static byte[] reply331 = null;
static byte[] reply421 = null;

    Socket sock = null;
    public FTPProtocol(Socket so)
    {
        sock = so; 
        reply220 = greeting.getBytes();
        reply331 = needPassword.getBytes();
        reply421 = closing.getBytes();
    }

    public void run()
    { 
        handleFTPClient(sock); 
    }

    void handleFTPClient(Socket sock)
    {
        InputStream is = null;
        OutputStream os = null;
        byte[] inBuffer = new byte[1024];

        try 
        {
            is = sock.getInputStream();
            os = sock.getOutputStream();
            os.write(reply220);
            int len = is.read(inBuffer);
            System.out.write(inBuffer, 0, len);
            os.write(reply331);
            len = is.read(inBuffer);
            System.out.write(inBuffer, 0, len);
            os.write(reply421);
            sock.close();
        } 
        catch (IOException e)
        {
            System.err.println(e.getMessage());
            return;
        }
    }
}
4

1 回答 1

1

我在这里错过了什么吗？您正在创建一个其类型实现的 on 对象Runnable（没有明显的原因）：

FTPProtocol client = new FTPProtocol(sock);

然后你什么也不做。

你的意思是用那个开始一个线程Runnable吗？或者将其传递给线程池：

ExecutorService exec = Executors.newFixedThreadPool(threadPoolSize);

while (true) {
   try {
      Socket sock = server.accept();
      exec.submit(new FTPProtocol(sock));
   } catch (IOException e) {
      System.err.println(e.getMessage());
      return;
   }
}

这将确保您不会启动更多线程，并且为每个对象调用threadPoolSize适当run的方法。FTPProtocol

于 2012-05-21T14:44:15.493 回答