EX06 custom calculator

 package com.company;

import java.util.Scanner;

class invalidInputException extends Exception{
    @Override
    public String toString() {
        return "Invalid input";
    }
}
class notDivideByZero extends Exception{
    @Override
    public String toString() {
        return "Cannot divide by zero";
    }
}
class maxInputException extends Exception{
    @Override
    public String toString() {
        return "Maximum input reached please enter value less and equal to 100000";
    }
}
class maxMultiplierReached extends Exception{
    @Override
    public String toString() {
        return "Stop please input is greater than 7000";
    }
}
public class CWH_87_Ex06 {
    public static void calculator() throws invalidInputException, notDivideByZero, maxInputException, maxMultiplierReached {
        System.out.println("Enter the two number");
        double c = 2.55d;
        Scanner sc = new Scanner(System.in);
        Scanner sc1 = new Scanner(System.in);
        double a = sc.nextDouble();
        double b = sc1.nextDouble();
        if (a==8 || a==9 || b==8 || b==9) {
            throw new invalidInputException();
        }
        if (a > 100000 || b > 100000) {
            throw new maxInputException();
        }
        System.out.println("First number--> " + a);
        System.out.println("Second number--> " + b);
        Scanner sc2 = new Scanner(System.in);
        System.out.println(" 1.Add \n 2.Substract \n 3.Multiply \n 4.Divide");
        System.out.println("Choose which operation you want");
        int d = sc2.nextInt();
        switch (d) {
            case 1:
                System.out.println("Addition is " + (a + b));
                break;
            case 2:
                System.out.println("Substraction is " +(a - b));
                break;
            case 3:
                if (a>7000 || b>7000) {
                    throw new maxMultiplierReached();
                }
                System.out.println("Multiplication is "+(a * b));
                break;
            case 4:
                if (b == 0) {
                    throw new notDivideByZero();
                }
                System.out.println("Division is "+(a / b));
                break;
            default:
                System.out.println("Choose appropriate operation!!");
        }
    }

    public static void main(String[] args) {
        try {
            calculator();
        }
        catch (invalidInputException e) {
            System.out.println(e.toString());
        }
        catch (notDivideByZero e) {
            System.out.println(e.toString());
        }
        catch (maxInputException e) {
            System.out.println(e.toString());
        }
        catch (maxMultiplierReached e) {
            System.out.println(e.toString());
        }
    }
}