Question

Anyone that could help me with the java.util.Scanner class?
I can’t figure out exactly how to use the delimiter method.

Input: teamA-teamB 4-5

Output: teamA:teamB:4:-5

Expected output: teamA:teamB:4:5

Piece of my code:

public void readResult()
{
    String team1, team2;
    int goals1, goals2;
    Scanner scanner = new Scanner(System.in);
    scanner.useDelimiter("\\s*-\\s*");
    if (scanner.hasNext())
    {
        team1 = scanner.next();
        scanner.useDelimiter("\\d*-\\d*");
        if(scanner.hasNext())
        {
            team2 = scanner.next().trim();
            scanner.useDelimiter("-");
            if(scanner.hasNext())
            {
                goals1 = scanner.nextInt();
                scanner.useDelimiter("\\n");
                if(scanner.hasNext())
                {
                    goals2 = scanner.nextInt();
                    System.out.println(team1 + ":" +  team2 + ":" + goals1 + ":" + goals2);
                    scanner.close();
                    return;
                }
            }
        }
    }
    scanner.close();
    System.out.println("bad format");
}

Answer 1

I would personally do this with a regex and group matching, but if you’re going to use a Scanner don’t focus on using delimiters, use the hasNext(String) and next(String) methods to match and retrieve the next pattern.

Regex with grouping example:

    String input  ="teamA-teamB 4-5";
    String team1, team2;
    int goals1, goals2;

    Matcher matcher = 
        Pattern.compile("(.*?)\\s*-\\s*(.*?)\\s*(\\d*)\\s*-\\s*(\\d*)")
        .matcher(input);
    if ( matcher.matches() ) {
        team1 = matcher.group(1);
        team2 = matcher.group(2);
        goals1 = Integer.parseInt(matcher.group(3));
        goals2  = Integer.parseInt(matcher.group(4));
        System.out.println(team1 + ":" +  team2 + ":" + goals1 + ":" + goals2);
    }