Regex to get first number in string with other characters

Question

I\'m new to regular expressions, and was wondering how I could get only the first number in a string like 100 2011-10-20 14:28:55. In this case, I\'d want it to

Answer 1

Try this to match for first number in string (which can be not at the beginning of the string):

    String s = "2011-10-20 525 14:28:55 10";
    Pattern p = Pattern.compile("(^|\\s)([0-9]+)($|\\s)");
    Matcher m = p.matcher(s);
    if (m.find()) {
        System.out.println(m.group(2));
    }