Why System.out.println can't print out a string value (in my particular case)?

Question

My program should ask users to enter some value and evetually those value should be printed out depending on the menu option choosen (in my case it's 3). I have used System.out.println("Your name: " + name); to print out the name inserted by user, but unfortunately it can't print out the name. The line is just left empty. Why so? How can I fix it.

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

    int userChoose;
    String name = null;
    int accNum = 0;
    double initiateAmount = 0;
    double newAmm = 0;

    double depOrWith = 0;
    System.out.println("WELCOME TO OUR BANK!\n\n"
            + "...................\n"
            + "...................\n\n"
            + "Choose your optiin:\n"
            + "1. Create new account\n"
            + "2. Deposit/withdraw\n"
            + "3. View details\n"
            + "4. Deleting an account\n"//not used yet
            + "5. View all the accounts\n"//not used yet
            + "6. Quit\n\n");
    System.out.println("*************\n"
            + "************");
    while (true) {
        userChoose = sc.nextInt();

        if (userChoose == 1) {

            System.out.println("Enter your full name:");

            name = sc.nextLine();
            sc.nextLine();

            System.out.println("Choose an account number:");

            accNum = sc.nextInt();

            System.out.println("Enter an initiating amount:");

            initiateAmount = sc.nextDouble();
            System.out.println("\n-----------\n"
                    + "------------");
        } else if (userChoose == 2) {

            System.out.println("Enter negative value to withdraw and positive to deposit");
            depOrWith = sc.nextInt();
            if (depOrWith < 0) {

               initiateAmount = initiateAmount + depOrWith;
            } else {

               initiateAmount = initiateAmount + depOrWith;
            }

            System.out.println("\n-----------\n"
                    + "------------");

        } else if (userChoose == 3) {

            System.out.println("Your name: " + name);
            System.out.println("Your account number: " + accNum);
            System.out.println("Your current balance: " + initiateAmount);
            System.out.println("\n-----------\n"
                    + "------------");
        } else if (userChoose == 6) {

            System.exit(0);

        }

    }

}

Did you execute the case 1 first? Because that is where the input is read and stored in `name` — thefourtheye, Apr 05 '15 at 10:04
Please learn to format your code correctly; this is wholly illegible. — Boris the Spider, Apr 05 '15 at 10:04
name is null in option 3, also use switch to make the conditions simpler. — Jack, Apr 05 '15 at 10:06
Boris the Spider, its easy to comment like this, but it's not easy to provide a good answer. By the way, can u tell me the wrong with my code formatting? which parth looks illigible and how to fix it? — Riyana, Apr 05 '15 at 10:28

score 2 · Accepted Answer · answered Apr 05 '15 at 10:07

After selecting the option and pressing Enter, the Scanner is not reading the newline. Afterwards when name = sc.nextLine(); is called it will only read the new line following the selected option and name will be assigned the empty string. To solve this, simply add a call nextLine after reading the selected option, and remove the duplicate nextLine when reading the name:

while (true) {
    userChoose = sc.nextInt();
    sc.nextLine();

    if (userChoose == 1) {

        System.out.println("Enter your full name:");

        name = sc.nextLine();

        System.out.println("Choose an account number:");

        ...

manouti, thanks, it makes a lots of sense now. – Riyana Apr 05 '15 at 10:17 — Riyana, Apr 05 '15 at 10:17

score 1 · Answer 2 · answered Apr 05 '15 at 10:16

1

Interchange the Blank nextLine() and the assigning one.

System.out.println("Enter your full name:");

        sc.nextLine();
        name = sc.nextLine();

        System.out.println("Choose an account number:");

        accNum = sc.nextInt();

answered Apr 05 '15 at 10:16

Anjula Ranasinghe

576
8
23

Anjula_Ranasinghe, thnak u, it also works i have tasted. Since i already got manouti's answer, i have accepted his. but anyway ur solution is simple and nice. – Riyana Apr 05 '15 at 10:20
Yes, His answer explains better. Thanks – Anjula Ranasinghe Apr 05 '15 at 10:36

score 0 · Answer 3 · answered Apr 05 '15 at 10:04

0

name is null. If the user selects three you haven't actually assigned a value to the name variable yet, that only happens if they choose 1

answered Apr 05 '15 at 10:04

MrB

757
6
26

score 0 · Answer 4 · answered Apr 05 '15 at 10:07

0

When you select the option 3 you're not setting the name value which defaults to null, so it's printing Your name: null

You need to read and assign name value if you want something to be printed.

answered Apr 05 '15 at 10:07

Neumann

311
3
15

Why System.out.println can't print out a string value (in my particular case)?

4 Answers4