scanner loop doesn't work for one field of method

Question

import java.util.Scanner;

public class EngineStorage {

    Engine[] engines = new Engine[3];

    Scanner scanner = new Scanner(System.in);

    public void fillArray(Engine[] engines) {
        String name;
        double vol;

        for (int i = 0; i < engines.length; i++) {

            System.out.println("name");
            name = scanner.nextLine();
            System.out.println("volume");
            vol = scanner.nextDouble();
        }
    }
}

when "i" is 0 it works fine but then loop is avoiding "name" variable when "i" is 1 and 2. The result is:

name
e32
volume   
2,5


name
volume
3


name
volume
3


Process finished with exit code 0

Yes, thank you so much for help :) – Daniel K Dec 20 '21 at 07:17 — Daniel K, Dec 20 '21 at 07:17

score 0 · Answer 1 · answered Dec 20 '21 at 07:21

0

nextDouble() does not skip to the next line, so the next time nextLine() is ran, it will read what is left on that line, which is nothing. You can consume the rest of this line with a blank newline like

for (int i = 0; i < engines.length; i++) {

        System.out.println("name");
        name = scanner.nextLine();
        System.out.println("volume");
        vol = scanner.nextDouble();
        scanner.nextLine(); //skip to next line
    }

answered Dec 20 '21 at 07:21

Ryan Millares

525
4
16

@Yunnosch my bad, did that text contain worse things? – Ryan Millares Dec 20 '21 at 09:15
@Yunnosch ah thanks for heads up, I'll try to pass posts like that through a translator first – Ryan Millares Dec 20 '21 at 09:18
Great. Have fun. Thanks for your contribution. – Yunnosch Dec 20 '21 at 09:18

scanner loop doesn't work for one field of method

1 Answers1