Question

我是度假的学生，我决定制作一个有趣的服务器应用程序。所以问题是：我的类 - Server.java - 是用ServerSocket创建的服务器，但是当我尝试构造一个Thread类 - ServerThread.java时 - 我以前从未见过的东西发生了。我调试了类，当我进入Server.java中调用的ServerThread的构造函数时，它不会进入ServerThread，而是进入ClassLoader.class。我认为这通常也会在某些时候发生，但现在只调用它而不是ServerThread的构造函数。

在过去的3天里，我一直在努力，几乎不停，但是因为皮特的爱，我无法让它发挥作用。

这是我的Server.java代码：

    public class Server
{
private ArrayList<Socket> sockets;
private ServerSocket ss;

// Constructor and while-accept loop all in one.
public Server( int port ) throws IOException
{   
    Runtime.getRuntime().addShutdownHook(new Thread()
    {
        @Override
        public void run()
        {
            try {
                ss.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    });

    // All we have to do is listen
    listen( port );
}

// Main routine
// Usage: java Server >port<
static public void main( String args[] ) throws Exception
{
    // Get the port # from the command line
    int port = 5003;
    // Create a Server object, which will automatically begin
    // accepting connections.
    new Server( port );
}

private void listen( int port ) throws IOException
{
    // Create the ServerSocket
    ss = new ServerSocket(port, 0, InetAddress.getByName("10.0.0.6"));
    // Tell the world we're ready to go
    System.out.println( "Listening on " + ss );

    sockets = new ArrayList<Socket>();

    // Keep accepting connections forever
    while (true)
    {
        // Grab the next incoming connection
        Socket s = ss.accept();
        // Tell the world we've got it
        System.out.println( "Connection from " + s );

        sockets.add(s);
        // Create a new thread for this connection, and then forget
        // about it
        new ServerThread( this, s );
    }
}

public void removeConnection(Socket socket) throws IOException
{
    synchronized (sockets) 
    {
        sockets.remove(socket);
        System.out.println("Closing connection at " + socket);
        socket.close();
    }
}

public void sendToAll(Socket s, String msg) throws IOException
{
    synchronized (sockets) 
    {
        for (int i = 0; i < sockets.size(); i++)
        {
            if (!sockets.get(i).equals(s))
            {
                new BufferedWriter(new OutputStreamWriter(sockets.get(i).getOutputStream())).write(msg);
            }
        }
    }
}
}

这是我的ServerThread.java代码：

    public class ServerThread extends Thread
{
private Server server;
private Socket socket;

public ServerThread( Server server, Socket socket )
{
    // Save the parameters
    this.server = server;
    this.socket = socket;
    // Start up the thread
    start();
}

// This runs in a separate thread when start() is called in the
// constructor.
public void run()
{
    try
    {
        // Create a DataInputStream for communication; the client
        // is using a DataOutputStream to write to us
        BufferedReader din = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        // Over and over, forever ...
        while (true)
        {
            String message = "";
            try
            {
                // ... read the next message ...
                message = din.readLine();
                // ... tell the world ...
                System.out.println( "Sending "+message );

                server.sendToAll(socket, message);
            }
            catch (SocketException ex)
            {
                break;
            }
            System.out.println("GG");
        }
    }
    catch( EOFException ie )
    {
        ie.printStackTrace();
        System.out.println("GG1");
    }
    catch( IOException ie )
    {
        // This does; tell the world!
        ie.printStackTrace();
        System.out.println("GG2");
    }
    finally
    {
        // The connection is closed for one reason or another,
        // so have the server dealing with it
        try {
            server.removeConnection( socket );
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}
}

我希望自己足够清楚......

Answer 1

如果您正在逐步调试并且达到需要当前卸载的类的new表达式，那么将进入类加载器。

这是正常行为。您可能需要多次退出才能返回代码。

Answer 2

确定。事实证明，构造函数被调用但程序在din.readLine（）中被挂起。我不知道为什么会发生这种情况，因为我在消息的末尾添加了一个'\ n'字符，所以我将BufferedReader和BufferedWriter对象改为java.io.DataInputStream和java.io.DataOutputStream并使用了readUTF（）和writeUTF（）方法，这个工作。谢谢大家的答案和时间:)。

类的构造函数不创建类

2 个答案: