JAVA: NoSuchElementException while function executing second time

Question

I'm working on simple Calculator app on Java. When user enter 0(which returns info no math operator), i want to restart my function. But when I do it throws NoSuchElementException when debug pointer comes to int operationInput = sc.nextInt(); Here is the my whole code block. I tried try catch but it stucks. Maybe it cannot re-identify a variable because it doesn't quit of that code block.

static Object mathOperators() {
        
        Scanner sc = new Scanner(System.in);
        System.out.print("Please enter a number for choosing operation(if you don't know what operation equals to which number click 0): ");
        int operationInput = sc.nextInt();
        sc.close();
        
        switch (operationInput) {
        case 0:
            System.out.println("1: Addition - 2: Subtraction - 3: Multiplication \n"
                    + "4: Division - 5: Modulus");
            return mathOperators();
        case 1:
            System.out.println(additionCalc());
            break;
        case 2:
            System.out.println(substractionCalc());
            break;
        case 3:
            System.out.println(multiplyCalc());
            break;
        case 4:
            System.out.println(divisionCalc());
            break;
        case 5:
            System.out.println(modulusCalc());
            break;
        default:
            System.out.println("Please enter a valid number");
            break;
        }
        
        return 0;
    }

Answer 1

You can use only one Scanner(System.in) in your app. You must close the scanner before calling "break" in your switch cases.