num = Keyboard.readInt(); java

[Techno3000]

import java.io.*;
import java.awt.*;
import hsa.Console;
 
public class Calculator
{
    static Console c;           
 
    public static void main (String [] args) throws IOException
 
    {
        c = new Console ();
 
        int num1, num2;
        int difference, sum, product, quotant;
        String awnser;
 
        DataInputStream keyboard = new DataInputStream (System.in);
 
        System.out.println ("Calculator Ready: enter a value");
        num1 = keyboard.readInt ();
        System.out.println ("Enter another value: ");
        num2 = keyboard.readInt ();
        System.out.println ("What would you like to do with there two values?");
        System.out.println ("add, subtract, multiply or divide?");
        awnser = keyboard.readLine ();
 
        difference = num1 - num2;
        sum = num1 + num2;
        product = num1 * num2;
        quotant = num1 / num2;
 
        if (awnser.equals ("subtract"))
        {
            System.out.println (num1 + " - " + num2 + " = " + difference);
 
        }
        else if (awnser.equals ("multiply"))
        {
            System.out.println (num1 + " x " + num2 + " = " + product);
 
        }
        else if (awnser.equals ("divide"))
        {
            System.out.println (num1 + " / " + num2 + " = " + quotant);
 
        }
        else
        {
            System.out.println (num1 + " + " + num2 + " = " + sum);
 
        }
 

This is a calculator simulation its not the whole thing but i just wanted to fix the error i am having before i move on. The language is java and the type of programs i am using are basic ones their ready anf Drjava.
The error message is:

 java.io.EOFException
        at java.io.DataInputStream.readInt(DataInputStream.java:363)
        at Calculator.main(Calculator.java:25)

[Ganon11]

If you are using Java 1.5 or later, try the Scanner.java class instead of DataInputStream.