import java.net.MalformedURLException;import java.rmi.RemoteException;import java.rmi.NotBoundException;public interface Naming {	public void rebind(String url,Chat server) 		throws RemoteException, MalformedURLException;	public java.rmi.Remote lookup(String url)		throws RemoteException,NotBoundException, MalformedURLException;	public void unbind(String url) 		throws RemoteException,NotBoundException, MalformedURLException;}