Question

For the URL http://questions/ask/stackoverflow.xhtml, the requirement is obtain stackoverflow.
What is the pattern used to obtain this page name?
The substring can be used but I read that the performance for pattern Matcher would be better.

Answer 1

For that particular URL you can use:

String url = "http://questions/ask/stackoverflow.xhtml";
String pname = url.split("/")[4].split("\\.")[0];

For the more useful (in terms of regex not in performance) Pattern based solution consider this:

String url = "http://questions/ask/stackoverflow.xhtml";
Pattern pt = Pattern.compile("/(?![^/]*/)([^.]*)\\.");
Matcher matcher = pt.matcher(url);
if(matcher.find()) {
    System.out.println("Matched: [" + matcher.group(1) + ']');
    // prints Matched: [stackoverflow]
}