how to stop while loop when taking input without words: "exit" etc

Question

I have to take inputs until EOF (white space or end of line). For example:

1
2
3
4
// end of taking input

I'm using Scanner to take inputs. I tried this solution.

    public static void main(String[] args) throws IOException {
        Scanner sc = new Scanner(System.in);
        ArrayList<String> password = new ArrayList<>();
        String input;

        while (!(input = sc.nextLine()).equals("")) {
            password.add(input);
        }

        boolean[] lengthValidation = lengthCheck(password);
        boolean[] passwordContainCheck = containCheck(password);

        print(lengthValidation, passwordContainCheck);
    }

I can't use this, due to uri does not take it variant of answer

while(true) {
   String input = sc.nextLine();
   
   if (input.equals(""))
       break;
}

It is not clear what you are trying to do. – Ioannis Barakos Sep 23 '20 at 15:56 — Ioannis Barakos, Sep 23 '20 at 15:56

WJS · Answer 1 · 2020-09-23T17:42:56.403

1

I have to take inputs until EOF (white space or end of line).

Try the following. One entry per line. Terminate with an empty line. You can store them in a list and use them when the loop terminates.

Scanner input = new Scanner(System.in);
String v;
List<String> items = new ArrayList<>();
while (!(v = input.nextLine()).isBlank()) {
    items.add(v);
}
System.out.println(items);

edited Sep 23 '20 at 17:42

answered Sep 23 '20 at 16:00

WJS

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it take all lines except last one. For example: 2 1 3 it take first 2, but doesn't third – Дамир Эсенов Sep 23 '20 at 16:12
sorry, yes, it's fine, but it doesn't solve my problem with uri ( it gave me next: ```Exception in thread "main" java.util.NoSuchElementException: No line found at java.util.Scanner.nextLine(Scanner.java:1540) at Main.main(Main.java:74)``` – Дамир Эсенов Sep 23 '20 at 16:23
You should provide more information on how you're using the input. – WJS Sep 23 '20 at 16:25

score 0 · Answer 2 · answered Sep 23 '20 at 16:07

Maybe this is what you are looking for, Scanner take input until it meets an empty line, then the loop stop

Scanner sc = new Scanner(System.in);
    ArrayList<String> password = new ArrayList<>();
    String input;

    while (true) {
        input = sc.nextLine();
        if (input.equals("")) break;
        password.add(input);
    }

how to stop while loop when taking input without words: "exit" etc

2 Answers2