如何获取一段 Url

Question

I have an URL https://example.com/A_segment/B_segment/ref=abc . Is there a way to extract B_segment out of it?

*The URL is not always the same but B_segment always follow A_segment and ahead of ref=.

Answer 1

Assuming URL can also be in form http://server.domain/what/ever/A_segment/xxxx/ref=123 and that you are interested in xxxx part you can use regex to find part /A_segment/(.+)/ref= . Part (.+) represents one or more of any characters and because of parenthesis it will be placed in group (here indexed as 1 since it is first (and only) group) to let us grab only match from that group.

Demo :

String url = "http://server.domain/what/ever/A_segment/xxxx/ref=123";
Pattern p = Pattern.compile("/A_segment/(.+)/ref=");
Matcher m = p.matcher(url);
if (m.find()){
    String result = m.group(1); //<-get match from group 1
    System.out.println(result); //Output: xxxx
} else {
    //here you can throw exception or return some default value in case of lack of match
}