Simple Calculator using TCP in Java

// Java program to illustrate Client Side Programming
// for Simple Calculator using TCP
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;

public class Calc_Client
{
    public static void main(String[] args) throws IOException
    {
        InetAddress ip = InetAddress.getLocalHost();
        int port = 4444;
        Scanner sc = new Scanner(System.in);

        // Step 1: Open the socket connection.
        Socket s = new Socket(ip, port);

        // Step 2: Communication-get the input and output stream
        DataInputStream dis = new DataInputStream(s.getInputStream());
        DataOutputStream dos = new DataOutputStream(s.getOutputStream());

        while (true)
        {
            // Enter the equation in the form-
            // "operand1 operation operand2"
            System.out.print("Enter the equation in the form: ");
            System.out.println("'operand operator operand'");

            String inp = sc.nextLine();

            if (inp.equals("bye"))
                break;

            // send the equation to server
            dos.writeUTF(inp);

            // wait till request is processed and sent back to client
            String ans = dis.readUTF();
            System.out.println("Answer=" + ans);
        }
    }
}

// Java program to illustrate Server Side Programming
// for Simple Calculator using TCP
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.StringTokenizer;

public class Calc_Server
{
    public static void main(String args[]) throws IOException
    {

        // Step 1: Establish the socket connection.
        ServerSocket ss = new ServerSocket(4444);
        Socket s = ss.accept();

        // Step 2: Processing the request.
        DataInputStream dis = new DataInputStream(s.getInputStream());
        DataOutputStream dos = new DataOutputStream(s.getOutputStream());

        while (true)
        {
            // wait for input
            String input = dis.readUTF();

            if(input.equals("bye"))
                break;

            System.out.println("Equation received:-" + input);
            int result;

            // Use StringTokenizer to break the equation into operand and
            // operation
            StringTokenizer st = new StringTokenizer(input);

            int oprnd1 = Integer.parseInt(st.nextToken());
            String operation = st.nextToken();
            int oprnd2 = Integer.parseInt(st.nextToken());

            // perform the required operation.
            if (operation.equals("+"))
            {
                result = oprnd1 + oprnd2;
            }

            else if (operation.equals("-"))
            {
                result = oprnd1 - oprnd2;
            }
            else if (operation.equals("*"))
            {
                result = oprnd1 * oprnd2;
            }
            else
            {
                result = oprnd1 / oprnd2;
            }
            System.out.println("Sending the result...");

            // send the result back to the client.
            dos.writeUTF(Integer.toString(result));
        }
    }
}