MatchResult groupCount() method in Java with Examples

Last Updated : 6 Jul, 2026

The groupCount() method of the MatchResult interface returns the number of capturing groups defined in a regular expression. It counts only the groups enclosed within parentheses () and does not include the entire matched pattern.

  • Counts only groups enclosed in parentheses ().
  • Does not count the complete match as a group.
  • Returns an integer value.
Java 
import java.util.regex.*;

public class Main {
    public static void main(String[] args) {

        Pattern pattern = Pattern.compile("(Java)(Programming)");
        Matcher matcher = pattern.matcher("JavaProgramming");

        System.out.println("Number of Groups: " + matcher.groupCount());
    }
}

Output
Number of Groups: 2

Explanation: The regular expression contains two capturing groups: (Java) and (Programming). Therefore, groupCount() returns 2.

Syntax

public int groupCount()

  • Parameters: This method do not takes any parameter.
  • Returns: An int representing the total number of capturing groups in the regular expression.

Example 1: Java code to illustrate groupCount() method

Java 
import java.util.regex.*;

public class GFG {
    public static void main(String[] args)
    {

        // Get the regex to be checked
        String regex = "(Geeks)";

        // Create a pattern from regex
        Pattern pattern
            = Pattern.compile(regex);

        // Get the String to be matched
        String stringToBeMatched
            = " GeeksForGeeks Geeks for For Geeks Geek";

        // Create a matcher for the input String
        MatchResult matcher
            = pattern
                  .matcher(stringToBeMatched);

        // Get the number of capturing groups
        // using groupCount() method
        System.out.println(matcher.groupCount());
    }
}

Output
1

Explanation: The regular expression contains one capturing group (Geeks). Hence, the groupCount() method returns 1.

Example 2

Java 
import java.util.regex.*;

public class GFG {
    public static void main(String[] args)
    {

        // Get the regex to be checked
        String regex = "GFG";

        // Create a pattern from regex
        Pattern pattern
            = Pattern.compile(regex);

        // Get the String to be matched
        String stringToBeMatched
            = "FGF GF FG FGF";

        // Create a matcher for the input String
        MatchResult matcher
            = pattern
                  .matcher(stringToBeMatched);

        // Get the number of capturing groups
        // using groupCount() method
        System.out.println(matcher.groupCount());
    }
}

Output
0

Explanation: The regular expression GFG does not contain any parentheses (), so there are no capturing groups. Therefore, groupCount() returns 0.

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