import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
 
public class Main{
 
	public static void main(String[] args) {
		String xPathData = "/hrdg:data/hrdg:meeting[@code='30J7Q']/hrdg:event[@id='2545525']/hrdg:selection[@id='31192111']";
		Pattern selectionIdPattern = Pattern.compile(".*/hrdg:selection\\[@id=\'(\\d+)\'\\]");
		Matcher matcher = selectionIdPattern.matcher(xPathData);
		if (matcher.find()) {
		     String selectionId = matcher.group(1); // now matches 31192111
		     System.out.println(selectionId);
		}
	}
}

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