Menu question

[John Powell]

In the following program the user has a simple menu with 3 choices. Two choices (a & b) will run specific methods and the final choice will quit the program. Is there a simple way to ask the user to press a key (once the called method is done) to return to the main menu, rather than returning automatically?

import java.util.Scanner;
 
public class TestMenu {
 
    public static void main (String [] args) {
        menu();
    }
    
    public static void menu() {
    
    Scanner kbd = new Scanner( System.in);
    
    do {
        System.out.println("a: Option 1");
        System.out.println("b: Option 2");
        System.out.println("q: QUIT");
        System.out.print("\nSelect an option: ");
        
        String input = kbd.next( );
            switch (input.charAt(0))
            {
            case 'a': case 'A':
                start();
                break;
            case 'b': case 'B':
                info();
                break;       
            case 'q': case 'Q':
                System.out.println( "Bye.");
                System.exit(0);
            default:
                System.out.println( input + " is invalid.\n");
            }
        } while (true);
    }
    
    public static void start() {
        //do something
        System.out.println("Press a key to return to menu");
    }
 
    public static void info() {
        //do something
        System.out.println("Press a key to return to menu"); 
    }
}
  

[Joel McNary]

From a command line, you can't get press ANY key, but you can do press ENTER to continue.

static pulic void delayScroll() throws the appropriate exceptions{
    char ugh = System.in.read();
    int numberAvailable = System.in.available();
    System.in.skip(numberAvailable);
}

The reason that you can't do any key is that System.in doesn't actually get anything from the commandline until enter is pressed.

[Sonny Gill]

That got me interested...after a bit of googling, this is what I can find -

http://www.javakb.com/Uwe/Forum.aspx/java/3108/JAVA-Unbuffered-access-to-stdin

I'll interpret that to mean that you want to be able to read from
System.in without waiting for the user to press enter - is that right?
If so, it's your OS console, not Java's buffering of System.in that
prevents it, and consequently unbuffering System.in (alone) won't let
you do it.

On unix-like platforms, you can use "stty -icanon min 1" to change
console mode so you can do character-at-a-time input. On other
operating systems, I have no idea.

I tried a few different combinations of input streams, only after using 'stty -icanon min 1' can I read input without waiting for an 'Enter'. This is on linux.

Is this kind of 'unbuffered' input from console enabled by default on windows? I remember writing C programs to read standard input without waiting for an 'Enter' on windows systems.