Matcher end(int) method in Java with Examples

The end(int group) method of Matcher Class is used to get the offset after the end index of the match result already done, from the specified group.

Syntax:

public int end(int group)

Parameters: This method takes a parameter group from which the offset after the end index of the matched pattern is required.

Return Value: This method returns the offset after the end index matched from the specified group.

Exception: This method throws:

• IllegalStateException if no match has yet been attempted, or if the previous match operation failed.
• IndexOutOfBoundsException if there is no capturing group in the pattern with the given group.

Below examples illustrate the Matcher.end() method:

Example 1:

// Java code to illustrate end() method

import java.util.regex.*;

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

        // Get the regex to be checked
        String regex = "(G*s)";

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

        // Get the String to be matched
        String stringToBeMatched
            = "GeeksForGeeks";

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

        // Get the current matcher state
        MatchResult result
            = matcher.toMatchResult();
        System.out.println("Current Matcher: "
                           + result);

        while (matcher.find()) {
            // Get the last index of match result
            System.out.println(matcher.end(1));
        }
    }
}

Output:

Current Matcher: java.util.regex.Matcher[pattern=(G*s) region=0,13 lastmatch=]
5
13

Example 2:

// Java code to illustrate end() method

import java.util.regex.*;

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

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

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

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

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

        // Get the current matcher state
        MatchResult result
            = matcher.toMatchResult();
        System.out.println("Current Matcher: "
                           + result);

        while (matcher.find()) {
            // Get the last index of match result
            System.out.println(matcher.end(0));
        }
    }
}

Output:

Current Matcher: java.util.regex.Matcher[pattern=(G*G) region=0,11 lastmatch=]
1
3
6
9
11

Reference: Oracle Doc