HOWTO: RMI without rmiregistry

Question

I'm putting this here for future common reference.
Usually you go start rmiregistry in the background, get your app to register with the registry and everything is fine. Internally RMI keeps an index of the objects being exported. It associates the index with a name inside an RMI registry. Without the registry you can export an object but noone knows what the index is so you're screwed.
This means that you've got to deploy rmiregistry and your application. What you want to do for smallish/simple applications is install both rmiregistry and your remote objects on the same port internal to your app.
Lets say we want our application on port 2004.
Registry localreg = LocateRegistry.createRegistry(2004);
MyService svc = new MyService(2004);
localreg.bind("FlikFlak",svc);
public class MyService extends UnicastRemoteObject
public MyService(int port)
super(port);
And thats it. One port with an internally bound rmiregistry. Other applications would continue as normal using that port for both your application and that object.
eg:
MyService svc = (MyService)Naming.lookup("//machine:2004/FlikFlak");

Answer 1

Hi!
I have tried the following example:
Interface:
=======
public interface RmiService extends Remote
    public void print(String txt) throws RemoteException;
}Rmi server:
=========
public class RmiServer extends UnicastRemoteObject implements RmiService
    public RmiServer(int port) throws RemoteException
        super(port);
    public void print(String txt) throws RemoteException
        System.out.println(txt);
    public static void main(String[] args)
        if (System.getSecurityManager() == null)
            System.setSecurityManager(new RMISecurityManager());
        try
            Registry rmiRegistry =  LocateRegistry.createRegistry(9999);
            RmiService rmiService = new RmiServer(9999);
            rmiRegistry.bind("RmiService", rmiService);
        } catch (Exception ex)
            ex.printStackTrace();
}Client:
=====
public class RmiClient
    public static void main(String[] args)
        if (System.getSecurityManager() == null)
            System.setSecurityManager(new RMISecurityManager());
        try
            RmiService remoteService = (RmiService) Naming.lookup("//192.1.50.109:9999/RmiService");
            remoteService.print("Hello World!!!");
        }  catch (Exception ex)
            ex.printStackTrace();
}Security policy file (security.txt):
==============
grant
    Permission java.security.AllPermission;
};I startet the server: java -Djava.security.policy=security.txt RmiServer, which seems to work, but when I start the client: java RmiClient, I get the following exception:
java.security.AccessControlException: access denied (java.net.SocketPermission 192.1.50.109:9999 connect,resolve)
     at java.security.AccessControlContext.checkPermission(AccessControlContext.java:269)
     at java.security.AccessController.checkPermission(AccessController.java:401)
     at java.lang.SecurityManager.checkPermission(SecurityManager.java:524)
     at java.lang.SecurityManager.checkConnect(SecurityManager.java:1026)
     at java.net.Socket.connect(Socket.java:446)
     at java.net.Socket.connect(Socket.java:402)
     at java.net.Socket.<init>(Socket.java:309)
     at java.net.Socket.<init>(Socket.java:124)
     at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:22)
     at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:128)
     at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:562)
     at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:185)
     at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:171)
     at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:313)
     at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
     at java.rmi.Naming.lookup(Naming.java:84)
     at RmiClient.main(RmiClient.java:21)
java
How can I make this example work?
Regards,
--Alex