Why does my scanner ask for input every three lines?

Question

Does anyone know why my scanner is asking for input every three lines, rather than every one line? If you run it, you will see that it asks the question first, but then doesn't for two more lines, then it asks the question again. How do I get it to ask a question every line, let alone store it in a linked list.

import java.util.Scanner;

public class StackCalc {

    public static StackLL stackll = new StackLL();

    public static void create() {

        String hold = new String();
        Scanner scanner = new Scanner(System.in);
        boolean running = true;
        while (true) {
        System.out.print("Enter number, math operation(+,-,*, or /), or Q to quit: ");
        hold = scanner.next();


        if (scanner.next().equals("Q") || scanner.next().equals("q")) {
            System.out.println(hold);
            break;
        }
    }

}

public static boolean checkInt(String s, int it){
    Scanner scan = new Scanner(s.trim());
    if(!scan.hasNextInt(it))
        return false;
    scan.nextInt(it);
    return !scan.hasNext();
    }

    public static void main(String args[]) {
        create();
    }
}

Any input would be awesome.

possible duplicate of [Skipping nextLine() after use nextInt()](http://stackoverflow.com/questions/13102045/skipping-nextline-after-use-nextint) — Alexis King, Jan 27 '15 at 00:40
@kirbyquerby It uses `next`, which will encounter the same behavior. — Alexis King, Jan 27 '15 at 00:41
This isn't your problem, but I"m betting this `(scanner.next().equals("Q") || scanner.next().equals("q"))` isn't what you want to do. That code will consume 2 tokens if the first character isn't a Q. — Falmarri, Jan 27 '15 at 00:42

sameer-s · Answer 1 · 2015-01-27T02:42:33.653

3

It is because you are using the method Scanner.next() three times:

hold = scanner.next()

scanner.next().equals("Q")

and scanner.next().equals("q")

Instead, only call it once by changing:

scanner.next().equals("Q") to hold.equals("Q")

and

scanner.next().equals(q") to hold.equals("Q")

edited Jan 27 '15 at 02:42

answered Jan 27 '15 at 01:03

sameer-s

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Why does my scanner ask for input every three lines?

1 Answers1