Java-Non Capturing Groups

Non Capturing Groups

Groups beginning with (?: are either pure, non-capturing groups that do not capture text and do not count towards the group total, or named capturing group.

Program

import java.util.regex.Pattern;
import java.util.regex.Matcher;

public class Javaapp {
  
    public static void main(String[] args) {
        
        Pattern pat = Pattern.compile("([0-9]{2})(?:[0-9]{2})([0-9]{4})");
        Matcher mat = pat.matcher("1022199009282010");
        
        while(mat.find())
        {
            System.out.println(mat.group(1)+"/"+mat.group(2));
        }
    }
}