/* Interface for a shared data structure between distributed processes. 
   The sample data structure is just a stack of strings.

   This is the only file that needs to be shared between server and
   clients.

   RMI service interfaces must extend the empty interface "Remote"
*/


import java.rmi.*;

public interface rmistack extends Remote
{
    // returns number of items in stack
    public int size() throws RemoteException; 

    // pushes s on stack
    public void push(String s) throws RemoteException; 

    // pops stack, returns null if stack empty
    public String pop() throws RemoteException;

    // like pop, but does not change stack:
    public String peek() throws RemoteException;
}


/*
To run example,
1. compile all three files: rmistack.java, stackimpl.java and stackclient.java
2. start rmiregistry on the server:  rmiregistry &
3. run the server-side program: java stackimpl &
4. run the client on the client host: java stackclient serverip
   where serverip is the ip address of the server. Use 127.0.0.1 for
   localhost.

The firewalls between client and server must allow connections to 
port 1099, which is the default rmiregistry port.  NAT boxes need to
correctly forward this port.
*/