Implement a simple calculator with basic four operations: +, -, *, /. It should run as follows:

Input: 1 + 2

Result: 3

Write the program with an exception handler that deals with illegal operations. Your program should display a message that informs the user of the error before exiting.

 For example: Input: 1 /  0

Result: Division by zero is illegal I

nput: A + 4

Result: Invalid operand type

 

this is what I have so far but its not working 

 

import java.util.*;

 

public class Calculator {

public static void main (String[] args) throws NumberFormatException{

 

@SuppressWarnings("resource")

Scanner keyboard = new Scanner(System.in);

 

 

do {

 

double result = 0;

int operand1 = 0;

int operand2 = 0;

String operator = "";

char op = ' ';

 

 

try{ 

System.out.print("Input first number: ");

operand1 =keyboard.nextInt();

System.out.print("Enter the operator ( + , - , * , / ): ");

operator = keyboard.next();

op = operator.charAt(0);

System.out.print("Input second number: ");

operand2 = keyboard.nextInt();

 

 

switch (op)

{

 

case '+':result = operand1 + operand2;

System.out.println("Answer: " + operand1 + ' ' + op + ' ' + operand2 + " = " + result );

break;

 

case '-': result = operand1 - operand2;

System.out.println("Answer: " + operand1 + ' ' + op + ' ' + operand2 + " = " + result );

break;

 

case '*': result = operand1 * operand2;

System.out.println("Answer: " + operand1 + ' ' + op + ' ' + operand2 + " = " + result );

break;

 

if(operand2==0)

{

throw new IllegalArgumentException();

}

case '/': result = operand1/(double)operand2;

System.out.println("Answer: " + operand1 + ' ' + op + ' ' + operand2 + " = " + result );

break;

default: 

System.out.println("Invalid operator");

break;

}

 

}

 

catch(IllegalArgumentException e){

System.out.println("Cannot divide by zero ");

}

catch(InputMismatchException ex){

 

 

System.out.println("The input is not an integer.");

System.out.println("Please reenter everything ");

 

 

}

}