Regular expression match group example

This is an example of how to use a regular expression match group. Using a regular expression to group matches of a String with a pattern implies that you should:

  • Compile a String regular expression to a Pattern, using compile(String regex) API method of Pattern.
  • Use matcher(CharSequence input) API method of Pattern to create a Matcher that will match the given String input against this pattern.
  • Use find() API method of Matcher to get the matches of the input with the pattern.
  • Use group(int group) API method to get the input subsequence captured by the given group during the previous match operation.

Let’s take a look at the code snippet that follows:  

package com.javacodegeeks.snippets.core;

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

 * REmatch -- demonstrate RE Match -> group()
public class MatchGroup {

    public static void main(String[] argv) {

  String pattern = "Q[^u]\d+\.";

  Pattern reg = Pattern.compile(pattern);

  String str = "Order QT300. Now!";

  Matcher matcher = reg.matcher(str);

  if (matcher.find()) {

System.out.println(pattern + " matches "" + + "" in ""

  + str + """);

  } else {

System.out.println("NO MATCH");



Q[^u]d+. matches "QT300." in "Order QT300. Now!"

This was an example of how to use a regular expression match group in Java.

Byron Kiourtzoglou

Byron is a master software engineer working in the IT and Telecom domains. He is an applications developer in a wide variety of applications/services. He is currently acting as the team leader and technical architect for a proprietary service creation and integration platform for both the IT and Telecom industries in addition to a in-house big data real-time analytics solution. He is always fascinated by SOA, middleware services and mobile development. Byron is co-founder and Executive Editor at Java Code Geeks.
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