With this example we are going to demonstrate how to use Matcher.group(int group) API method to get the input subsequence captured by the given group during the previous match operation. In short, to use group(int group) API method of Matcher 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
group(int group)API method to get subsequence captured by the group during the previous match, or null if the group failed to match part of the input.
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;
public class SubGroup {
public static void main(String args[]) {
Pattern pattern = Pattern.compile("\w(\d)");
String str = "J9 is my favorite";
Matcher m = pattern.matcher(str);
if (m.find()) {
String tmp = m.group(0);
System.out.println(tmp);
tmp = m.group(1);
System.out.println(tmp);
}
}
}
Output:
J9
9
This was an example of Matcher.group(int group) API method in Java.
