我想以下几点可能会有所帮助：

public void test() {
    int number1 = 0;
    int number2 = 0;
    int expected = 0;

    System.out.println("Enter first number");
    int state = 0;
        Scanner scanner = new Scanner(System.in);
        String input = "";

        while(!input.equals("E")) {
            input = scanner.nextLine();
            input = input.toUpperCase();
            if (!input.equals("") && Character.isDigit(input.charAt(0))){
                switch(state) {
                case 0:
                    number1 = Integer.parseInt(input);
                    System.out.println("Enter second number");
                    break;
                case 1:
                    number2 = Integer.parseInt(input);
                    System.out.println("Enter expected result");
                    break;
                case 2:
                    expected = Integer.parseInt(input);
                    System.out.println("Result: " + (number1 + number2) +
                            " | Expected: " + expected + System.lineSeparator());
                    System.out.println("Enter first number");
                    state = -1;
                    break;
                default:
                    break;
                }
                state++;
            }
        }
        scanner.close();
        System.out.println("Exiting");
    }