连接在127.0.1.1 java RMI被拒绝

Question

I am new at Java RMI technology. I have a problem that already other programmers had, but I was not able to understand what they did in the tutorials in order to solve it. I have implemented the game "tic tac toe" with Java RMI. Here the ControllerServer code

public ControllerServer() {

    try {
        game = new GameImpl();
        BoardView view = new BoardView(this);
        viewUpdater = new ServerViewUpdaterImpl(view);

        Game gameStub = (Game) UnicastRemoteObject.exportObject(game, 1099);
        ServerViewUpdater serverViewStub = (ServerViewUpdater) UnicastRemoteObject.exportObject(viewUpdater, 1099);

        Registry registry = LocateRegistry.createRegistry(1099);

        registry.rebind("TTTGame", gameStub);
        registry.rebind("TTTServerView", serverViewStub);


    } catch (Exception e) {
        e.printStackTrace();
    }
}

and here the ControllerClient

public ControllerClient() {
    try {

        BoardView view = new BoardView(this);
        localView = new ClientViewUpdaterImpl(view);

        String address = JOptionPane.showInputDialog("Insert server's address: ");

        Registry registry = LocateRegistry.getRegistry(address, 1099);

        game = (Game) registry.lookup("TTTGame");
        remoteView = (ServerViewUpdater) registry.lookup("TTTServerView");
        remoteView.registerClientView(localView);


    } catch (Exception e) {
        e.printStackTrace();
    }

}

It works locally, by inserting "localhost" "127.0.0.1" or my external network IP. It does not work if client and server run on different machines.

I got the exception " connection refused by 127.0.1.1 ". I do not understand why they are trying to use a localhost address at some point of the execution.

Answer 1

as the other said, this is beach your IP is set to 127.0.1.1

Run a ipconfig -a to see what's the IP address of your host.

Then edit the /etc/hosts file and instead of this line 127.0.1.1 "name of the host" replace the 127.0.1.1 with the IP of your machine .

This should work.

You can always validate the IP that the rmi server is listening to, by executing:

String hostname = InetAddress.getLocalHost().getHostAddress();
Log.info("this host IP is " + hostname);

If you overwrite the /etc/hosts file with the correct IP, then everything should work.

Answer 2

You got the address wrong when you called getRegistry(). You need to supply the address of the server host. There is normally no RMI Registry running in a client host.

Answer 3

This is because your the IP is most likely wrong. It is 127.0.0.1 and not 127.0.1.1 . You can try it with localhost as well.