java - 类的构造函数不创建类

Question

我是一名正在度假的学生，我决定制作一个服务器应用程序来娱乐。所以问题是:我的类(class) - Server.java - 是使用 ServerSocket 创建的服务器，但是当我尝试构造 Thread 类时 - ServerThread.java - 我以前从未见过的事情发生了。我调试了该类，当我进入 Server.java 中调用的 ServerThread 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个时候发生，但现在只有这个被调用，而不是 ServerThread 的构造函数。 .

在过去的三天里，我一直在为此苦苦挣扎，几乎不间断，但出于对皮特的爱，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();
        }
    }
}
}

我希望我已经说得足够清楚了......

Answer 1

如果您正在逐步调试，并且到达需要当前卸载的类的 new 表达式，您将进入类加载器。

这是正常行为。您将不得不退出(可能需要多次)才能返回代码。