Question

it seems that I am completely blocked because I do not know why this code always prints “true”:

public class Main {

    public static void main(String[] args)  {   
    Pattern p = Pattern.compile("[1-9]{1,2}");
    Matcher m = p.matcher("1234567");
    System.out.println(m.find());   
    }

}

Answer 1

Matcher.find will perform a partial match on the String so will always find a digit to match. You need to use Matcher.matches() to match the full String:

System.out.println(m.matches());