Question

This is for coursework. I’ve built the whole program, and it does everything right, apart from this one thing.

I have a class called ‘Schedule’ this method is at the very end of schedule:

public void bookSeatMenu()
    {   boolean leaveBookSeatMenu = false;
        String seatBookingMenuStr;
        int seatBookingMenuInt = 14;
        boolean isInteger = false;
        Scanner input = new Scanner(System.in);
        System.out.println("Press 1 to add an individual booking, 2 to cancel a booked seat or 3 to go back");

        seatBookingMenuStr = input.nextLine();
                  try {
                      seatBookingMenuInt = Integer.parseInt(seatBookingMenuStr);
                      isInteger = true;
                    }

                    catch (NumberFormatException e) {

                    }
                  switch (seatBookingMenuInt) {
                      case 1: 
                        bookSeat();
                        break;
                      case 2:
                        cancelSeat();
                        break;
                      case 3:
                        leaveBookSeatMenu = true;
                        break;
                      default:
                        System.out.println("Invalid Choice");
                    } while (leaveBookSeatMenu == false);

                } 

I know you all know what a switch menu looks like, but I thought I’d throw it in there anyway, in case (pardon the pun) I’m going wrong here.

Moving on, I have the bookSeat method, this is where the user books a seat (which works fine). Then afterwards it displays the bookSeatMenu() just it displays the menu. But then it won’t go back to the previous one.

   public void bookSeat()
   {
       Scanner input = new Scanner(System.in);
       boolean isSeatBooked = true;
       showSeatPlan();
       int seatNum = 0;
       int rowNum = 90;
       int columnNum = 16;
       boolean isInt = false;

       while (isSeatBooked == true)
       {
           System.out.println("Please pick column of a seat to book");
           columnNum = input.nextInt();

           System.out.println("Please pick row of a seat to book");
           rowNum = input.nextInt();


           seatNum = (columnNum + ((rowNum) * 15));

           if (seats[seatNum] == false)
           {
               isSeatBooked = false;
           }
           else
           {
               System.out.println("This seat is already booked");
            }
       }

       seats[seatNum] = true;


       System.out.println("");
       bookSeatMenu();
   }

Now not for love nor money am I able to get it to go back to the previous menu after it’s booked a seat.

Basically the process is:

Book a seat –> go to bookSeatMenu –> press 4 to go back –> Arrive at previous menu.

If I don’t book a seat, the program will happily go back to the menu before hand, but after, it just keeps on going on to a new line in the command prompt, not doing anything else, no error etc.

I’m pretty tempted to say this might be a problem with BlueJ, although a bad workman blames his tools, and I don’t wanna be ‘that guy’

I also need to make a ‘testing class’ – having never used a ‘testing class’ before, and the assignment asking us to look in the ‘textbook’ which noone bothered to buy, I actually have no idea!

Answer 1

There’s no switch...while so I assume your problem is as soon you do choose 3, you end up in while(true); which is an infinite loop.

correct pseudo-code:

do {
   // read System.in

   // handle menu options with your switch
} while(...)

By the way, design is bad IMHO, you should try to think about your model (in your case I would see something like Room, Seat, Scheduler, Menu) and make those object interact with each others :

public class Room {
    private Seat[][] seats;
    public String toString() {
        // like showSeatPlan() using toString() of Seat
    }
}

public class Seat {
    private int row, column;
    private boolean isBooked;
    public void book() { /* ... */ }
    public void cancel() { /* ... */ }
    public String toString() { /* "X" or " " */ }
}

public final class Scheduler {
   // "main class" with a "main" method
}

public class Menu {
    private Room room;
    public String toString() {
        // print out menu
    }
    public void bookSeat() { /* ... */ }
    public void cancelSeat() { /* ... */ }
}

(something like that)

For the test part, each class have a test class and each method have a test method, as an example, for Seat:

public class Seat {
    public void book() { 
        if (this.isBooled) {
           throw new CannotBookException("seats is taken!");
        }
        this.isBooled = true;
    }
}

public class SeatTest {
    @Test // when I book a seat, it's markedas booked.
    public void testBook() {
        final Seat seat = new Seat();
        seat.book();
        assertTrue(seat.isBooked)
    }

    @Test(expected = CannotBookException.class) // when I book an already booked seat, I get an exception.
    public void testBookAlreadBooked() {
        final Seat seat = new Seat();
        // book the seat
        seat.book();
        assertTrue(seat.isBooked)

        // try to book again
        seat.book();
    }
}