Java - Mathematical Operations using RMI

	import java.rmi.*;
	import java.rmi.server.*;

	public interface MathServerIntf extends Remote {   

	    public int add(int a, int b) throws RemoteException;

	    public int subtract(int a, int b) throws RemoteException;

	    public int multiply(int a, int b) throws RemoteException;

	    public int divide(int a, int b) throws RemoteException;
	}

	import java.rmi.*;
	import java.rmi.server.*;

	public class MathServerImpl extends UnicastRemoteObject implements MathServerIntf {

	    public MathServerImpl() throws RemoteException {
	    }

	    public int add(int a, int b) throws RemoteException {
	        return a+b;
	    }

	    public int subtract(int a, int b) throws RemoteException {
	        return a-b;
	    }

	    public int multiply(int a, int b) throws RemoteException {
	        return a*b;
	    }

	    public int divide(int a, int b) throws RemoteException {
	        if(b==0) {
	            return -1;
	        } else {
	            return a/b;
	        }
	    }
	}

	import java.rmi.*;
	import java.rmi.server.*;

	public class MathServer {

	    public static void main(String[] args) {
	        try {
	            MathServerImpl mathServerImpl = new MathServerImpl();
	            Naming.rebind("MathServer", mathServerImpl);
	        } catch(Exception exp) {
	            exp.printStackTrace();
	        }
	    }
	}

	import java.rmi.*;
	import java.rmi.server.*;
	import java.io.*;

	public class MathClient {

	    public static void main(String[] args) {
	        try {
	            String mathServerURL = "rmi://" + args[0] + "/MathServer";
	            MathServerIntf mathServerIntf = (MathServerIntf)
	                Naming.lookup(mathServerURL);
	            BufferedReader bufferedReader = new BufferedReader(
	                                new InputStreamReader(System.in));

	            while(true) {
	           
	            System.out.println("\n\n1. Addition\n2. Subtraction\n3. Multiplication\n4. Division\n5. Exit\n");
	            System.out.println("Enter your option...");
	            int option = Integer.parseInt(bufferedReader.readLine());
	           
	            int number1 = 0, number2 = 0;

	            if(option>=1 && option <=4) {
	                System.out.println("Enter the first number...");
	                number1 = Integer.parseInt(bufferedReader.readLine());

	                System.out.println("Enter the second number...");
	                number2 = Integer.parseInt(bufferedReader.readLine());
	            }

	            switch(option) {
	                case 1: System.out.println("Sum...");
	                    System.out.println(
	                        mathServerIntf.add(number1, number2));
	                    break;

	                case 2: System.out.println("Difference...");
	                    System.out.println(
	                        mathServerIntf.subtract(number1, number2));
	                    break;
	       
	                case 3: System.out.println("Product...");
	                    System.out.println(
	                        mathServerIntf.multiply(number1, number2));
	                    break;
	       
	                case 4: System.out.println("Quotient...");
	                    System.out.println(
	                        mathServerIntf.divide(number1, number2));
	                    break;

	                case 5: System.exit(0);

	                default: System.out.println("Enter a valid option...");               
	            }

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