Doubt on a program using Scanner

[Rajiv Rai]

Hi,

I ran the following code to understand how Scanner works.

import java.util.Scanner;

class Console {

  static Scanner sc = new Scanner(System.in);

  public static boolean askYorN(String prompt) {
    while (true) {
      String answer;
      System.out.print("\n" + prompt + " (Y or N) ");
      answer = sc.next();
      if (answer.equalsIgnoreCase("Y"))
        return true;
      else if (answer.equalsIgnoreCase("N"))
        return false;
    }
  }
}

public class Scanner2 {
  public static void main(String[] args) {
    while (Console.askYorN("Keep going?")) {
      System.out.println("!");

    }
  }
}

The following is a sample output for the above code

Keep going? (Y or N) 6

Keep going? (Y or N) g

Keep going? (Y or N) n



Am not able to understand how the program re-ran when i entered 6 as input first time
and pressed Enter.. According to me it should run just once.

Thanks.

[Winston Gutkowski]

Rajiv Rai wrote:Am not able to understand how the program re-ran when i entered 6 as input first time
and pressed Enter.. According to me it should run just once.

Why? What do you think while(true) does?

Tip: Add
else System.out.println("Invalid response");
at line 16, and see what it produces.

Winston