CalculatorRunner

CalculatorRunner.java

import java.util.Scanner;

public class CalculatorRunner
{
 public static void main(String[] args)
 {
  int num1;
  int num2;
  char operator;
  boolean valid;
  
  //instantiate a Scanner
  Scanner scan = new Scanner(System.in);

  //prompt the user for the operator (how do you read in a character?)
  System.out.println("Enter the operator:");
  operator = scan.next().charAt(0);

  //setup a set of conditions below to determine if the operator is valid
  if(operator == '+' || operator == '-' || operator == '*' || operator == '/') // if the operator is valid, set boolean valid = true
  {
   valid = true;
  } //else, it stops the program
  //get the remaining inputs from the user
  System.out.println("Enter the first operand:");
  num1 = scan.nextInt();
  System.out.println("Enter the second operand:");
  num2 = scan.nextInt();
  
  //check for division by zero
  if(num2 == 0 && operator == '/') //if the operator is 0 and the second number is 0, print a statement
  {
   System.out.println("You can't divide by zero.");
   valid = false;
  }
  else{ valid=true; } //if not dividing by 0, valid is true
  //instantiate Calculator object with the values entered by the user
  if(valid == true) //only if valid = true, if not, the program stops.
  {
   Calculator calculator = new Calculator(num1, num2, operator);
   System.out.println(calculator.toString());
  }
 }
}