Is there a way for me to be able to use the same scanner for both a System.in Input and for a FileInputStream Input?

Question

Is there a way for me to be able to use the same scanner for both a System.in Input and for a FileInputStream Input?

Here is how I have initialized the scanner in my main class:

public class Nimsys {
    public static Scanner keyboardIn;

    static {
        keyboardIn = new Scanner(System.in);
    } ...

In the main class Nimsys here is how I get input:

String inputString1 = keyboardIn.nextLine();

In another class here is how I use the scanner from Nimsys:

int inputInt1 = Nimsys.keyboardIn.nextInt();

But now in my main class Nimsys I am trying to scan in a whole file - so far I have used another scanner, as you can see in the code below. However, is it possible to have it all done by the original scanner?

try
        {
            inputStream = new Scanner(new FileInputStream("file.txt"));
        }
        catch (FileNotFoundException e)
        {
            System.out.println("File morestuff.txt was not found");         
        }
        String[] reopenPlayers = new String[100];
        int i = 0;
        while(inputStream.hasNextLine()){
            reopenPlayers[i]=inputStream.nextLine();
        System.out.println(reopenPlayers[i]);
        }

Thanks a lot!

Tom

Answer 1

If I understand your question (not that I think a global variable is a great solution), you could change (and perhaps rename)

keyboardIn = new Scanner(System.in);

to something like

try {
    keyboardIn = new Scanner(new FileInputStream("file.txt"));
} catch (FileNotFoundException e) {
    System.out.println("file \"file.txt\" not found");
    e.printStackTrace();
}

and then remove the try-catch from

inputStream = new Scanner(new FileInputStream("file.txt"));

and modify it to something like

inputStream = Nimsys.keyboardIn;

(or replace inputStream with Nimsys.keyboardIn ^{_{and not to be prescriptive but perhaps rename Nimsys.keyboardIn to Nimsys.in}}). Hopefully you're using an IDE that supports refactoring.