gistfile1.txt

package oot.lab8;
public class Calculator implements MathCalculator {
    private double operand1;
    private double operand2;
    public Calculator(double operand1, double operand2){
        this.operand1 = operand1;
        this.operand2 = operand2;
    }
    public double add() {
        return operand1 + operand2;
    }
    public double minus() {
        return operand1 - operand2;
    }

    public void compare() {
        if(operand1 > operand2) {
            System.out.println(operand1 + " > " + operand2 + " : " + (operand1-operand2));
        } else {
            System.out.println(operand1 + " <= " + operand2 + " : " + (operand2-operand1));
        }
    }
}

package oot.lab8;

/**

• Created by Bhuridech Sudsee.
  */
  public interface MathCalculator {
  public double add();
  public double minus();
  }

package oot.lab8;

/**
 * Created by Bhuridech Sudsee.
 */
public interface MathCalculator {
    public double add();
    public double minus();
}

package oot.lab8;

import java.util.Scanner;

/**
 * Created by Bhuridech Sudsee.
 */
public class Lab8Sec1 {
    public static void main(String args[]){
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter number with operator : ");
        String calText = scanner.nextLine();
        String[] calTextSplit = calText.split(" ");
        double firstOperand = Double.valueOf(calTextSplit[0]);
        String operator = calTextSplit[1];
        double secondOperand = Double.valueOf(calTextSplit[2]);
        Calculator c = new Calculator(firstOperand, secondOperand);
        switch (operator){
            case "ADD":
                System.out.println(calText + " = "+ c.add());
                break;
            case "MINUS":
                System.out.println(calText + " = "+ c.minus());
                break;
        }
        c.compare();
    }
}