import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception {
String regex = "(?<=http://)\\S+";
Pattern pattern = Pattern.compile(regex);
String candidate = "The rntsoft website can be found at ";
candidate += "http://www.rntsoft.com. There, ";
candidate += "you can find information about some of ";
candidate += "best example codes";
Matcher matcher = pattern.matcher(candidate);
while (matcher.find()) {
String msg = ":" + matcher.group() + ":";
System.out.println(msg);
}
}
}