0

我不知道为什么我的程序在调试时工作并且在正常执行中失败。

我已经设置了一个简单的服务器来通过套接字提供文件。当客户端连接时，一个线程开始执行此任务，但它失败了。我收到“套接字已关闭”错误。

这是家庭作业：在我弄清楚为什么会发生这种情况并且只是想朝着正确的方向轻推之前，我无法前进。

为了让它在调试中工作，我在它接受客户端连接的服务器类中设置了断点。

提前致谢。

public class File_Server {

    private static ServerSocket servsock;

    public static void main(String[] args) throws IOException 
    {
        // create socket
    try {
        servsock = new ServerSocket(4444);
    } catch (Exception e) {
        System.out.println("Port already in use.");
        System.exit(1);
    }

    while (true) {
        System.out.println("Waiting...");
        try (Socket sock = servsock.accept()) {
            System.out.println("Accepted connection : " + sock);

            Thread t = new Thread(new CLIENTConnection(sock));

            t.start();

        } catch (Exception e) {
            System.out.println("Cannot accept connection.");
            }
        }
    }
}



public class CLIENTConnection implements Runnable {

    private Socket client;

    CLIENTConnection(Socket client) {
        this.client = client;
    }

    @Override
    public void run() 
    {
        try {
            FileInputStream fis = null;         
            // sendfile
            File myFile = new File("studentData.txt");
            byte[] mybytearray = new byte[(int) myFile.length()];
            fis = new FileInputStream(myFile);
            BufferedInputStream bis = new BufferedInputStream(fis);
            bis.read(mybytearray, 0, mybytearray.length);
            OutputStream os = client.getOutputStream();
            System.out.println("Sending...");
            os.write(mybytearray, 0, mybytearray.length);
            os.flush();
            fis.close();
        } catch (IOException ex) {
            Logger.getLogger(CLIENTConnection.class.getName()).log(Level.SEVERE, null, ex);
        } 
    }
}



public class File_Client {

    private static long start = System.currentTimeMillis();
    private static int bytesRead;
    private static int current = 0;

    public static void main(String[] args) throws IOException 
    {
        int filesize = 60223861; // filesize temporary hardcoded

        try (Socket sock = new Socket("127.0.0.1", 4444)) {
            System.out.println("Connecting...");

            // receive file
            byte[] mybytearray = new byte[filesize];
            InputStream is = sock.getInputStream();
            FileOutputStream fos = new FileOutputStream("studentData-received.txt");
            try (BufferedOutputStream bos = new BufferedOutputStream(fos)) {
                bytesRead = is.read();//.read(mybytearray, 0, mybytearray.length);
                current = bytesRead;

                do {
                    bytesRead =
                            is.read(mybytearray, current, (mybytearray.length - current));
                    if (bytesRead >= 0) {
                        current += bytesRead;
                    }
                } while (bytesRead > -1);

                bos.write(mybytearray, 0, current);
                bos.flush();
                long end = System.currentTimeMillis();
                System.out.println("Time taken " + (end - start) + " milliseconds");
            }
        } catch (Exception e) {
            System.out.println("Cannot connect to server.");
        }
    }
}
4

1 回答 1

2

您犯了忽略 read() 结果的常见错误。它返回实际读取的字节数，或在 EOS 处返回 -1。Java中复制流的方法如下：

while ((count = in.read(buffer)) >= 0)
{
  out.write(buffer, 0, count);
}

其中'count'是一个int。

于 2013-01-26T04:12:03.540 回答