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RMI Server and Client implementation

1. Interface
  • interface extends Remote class
  • every method throws RemoteException
package com.rmi;

import java.rmi.Remote;
import java.rmi.RemoteException;
import java.util.Date;

public interface RmiInterface extends Remote {

 Date getDate() throws RemoteException;
}
2. RMI server implementation
  • class extends UnicastRemoteObject
  • class implements custom RmiInterface
  • class creates RMI registry and binds it to localhost and specified port
package com.rmi.server;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.rmi.AlreadyBoundException;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import java.rmi.server.UnicastRemoteObject;
import java.util.Date;

import com.rmi.RmiInterface;

public class RMIServer extends UnicastRemoteObject implements RmiInterface {

 protected RMIServer() throws RemoteException, AlreadyBoundException,
   UnknownHostException {
     
  String registryHost = InetAddress.getLocalHost().toString();
  String registryName = "serverRMI";
  int registryPort = 1234;
  
  System.out.println("Starting RMI server on host: " + registryHost
    + ", port: " + registryPort + " with name: " + registryName);
  
  Registry registry = LocateRegistry.createRegistry(registryPort);
  registry.bind(registryName, this);
 }

 @Override
 public Date getDate() {
  return new Date();
 }

 public static void main(String[] args) throws RemoteException,
   UnknownHostException, AlreadyBoundException {
  RMIServer server = new RMIServer();
 }
}
3. RMI client implementation
  • class gets RMI registry
  • class invokes RMI server method
package com.rmi.client;

import java.rmi.NotBoundException;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import java.util.Date;

import com.rmi.RmiInterface;

public class RMIClient {

 public static void main(String[] args) throws RemoteException,
   NotBoundException {
   
  String registryHost = "127.0.0.1";
  String registryName = "serverRMI";
  int registryPort = 1234;
  
  Registry registry = LocateRegistry.getRegistry(registryHost,
    registryPort);
  RmiInterface rmiServer = (RmiInterface) registry.lookup(registryName);
  Date date = rmiServer.getDate();
  
  System.out.println("Date from RMI server: " + date);
 }
}
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