Question

Suppose I have a string:
String message = “you should try http://google.com/“;

Now, I want to send “http://google.com/” to a new
String url

What I want to do is:
check if a “word” in the string begins with “http://” and extract that word, where a word is
something that’s surrounded by spaces (general english definition of word).

I have no idea how to extract the string, and the best I can do is use startsWith on the string. How to I use startsWith on a word, and extract the word?
Sorry if this is a little bit difficult to explain.
Thanks in advance!

EDIT: Also, what should I do to extract the word from the REGEX operation? And how should I handle it if there is more than 1 url in the string?

Answer 1

Use Pattern & Matcher classes.

String str = "blabla http://www.mywebsite.com blabla";
String regex = "((https?:\\/\\/)?(www.)?(([a-zA-Z0-9-]){2,}\\.){1,4}([a-zA-Z]){2,6}(\\/([a-zA-Z-_/.0-9#:+?%=&;,]*)?)?)";
Matcher m = Pattern.compile(regex).matcher(str);
if (m.find()) {
    String url = m.group(); //value "http://www.mywebsite.com"
}

This regex will work for http://..., https://... and even www... URLs. Others regex can be easily found on the net.