by pass do while loop

Question

I wondering is it possible to skip past a do while loop or even exit a method halfway through it if certain conditions are met? Heres an example of what I mean ( everything works in this )

  public void loanBook() {
            Scanner input = new Scanner(System.in);
            boolean successful = false;
            boolean bookExists = false;
            boolean memberIDExists = false;
            boolean memberCurrentlyLoaningBook = false;
            int memberID = 0;
            System.out.println("You must be a member of the library to loan out a book");
            do {
                System.out.println("\nPlease enter your memberID (Press 9 to exit)");
int bookID = input.nextInt();
                input.nextLine();
                if (bookID == 9) {
                    successful = true;
                }
                memberID = input.nextInt();
                for (int i = 0; i < members.size(); i++) {
                    if (memberID == members.get(i).getMemberID()) {
                        memberIDExists=true;
                        if(members.get(i).isCurrentlyLoaningBook()==false){
                            successful = true;
                            memberCurrentlyLoaningBook=true;
                        }
                    } 
                }

                if(!memberCurrentlyLoaningBook){
                    System.out.println("This member is currently loaning a book");
                }

                if (!memberIDExists) {
                    System.out.println("This member ID does not exist");
                }

            } while (successful == false);

EDIT do while loops that are in the same method

do { these other do while loops are after this first one and do other things } while (); ( I haven't included what they do as it takes up too do { much space) } while();

I have an option here to exit to the main menu, but i also have a do while loop after this, so whenever I enter 9 it just exits the current to while loop and goes on to the next one, is there anyway that I can skip past all the proceeding do while loops after I press 9, or even exit the method?

Answer 1

In your case continue or break could be useful. But if you want to exit the method you could just do it with return .

Answer 2

Try this, I have added break; when user enter "9" as an input. It will then come out of the do while loop.

            do {
                System.out.println("\nPlease enter your memberID (Press 9 to exit)");
                int bookID = input.nextInt();
                input.nextLine();
                if (bookID == 9) {
                    successful = true;
                    break;
                }

EDIT:

Yes to Check for the next loop, add a condition with that loop

loop(your original condition && !successful)
{
 }

EDIT 2: TO come out of the loop and avoid other do while loops in the method, you can just return; It will take back the control of the program through which this method was called.

do {
                    System.out.println("\nPlease enter your memberID (Press                       9 to exit)");
                    int bookID = input.nextInt();
                    input.nextLine();
                    if (bookID == 9) {
                        successful = true;
                       return;
                    }