Pattern matcher() method in Java with examples

The java.util.regex package of java provides various classes to find particular patterns in character sequences.

The pattern class of this package is a compiled representation of a regular expression. The matcher() method of this class accepts an object of the CharSequence class representing the input string and, returns a Matcher object which matches the given string to the regular expression represented by the current (Pattern) object.

Example

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class MatcherExample {
   public static void main(String args[]) {
      //Reading string value
      Scanner sc = new Scanner(System.in);
      System.out.println("Enter input string");
      String input = sc.nextLine();
      //Regular expression to find vowels
      String regex = "[aeiou]";
      //Compiling the regular expression
      Pattern pattern = Pattern.compile(regex);
      //Retrieving the matcher object
      Matcher matcher = pattern.matcher(input);
      if(matcher.find()) {
         System.out.println("Given string contains vowels");
      } else {
         System.out.println("Given string does not contain vowels");
      }
   }
}

Output

Enter input string
RHYTHM
Given string does not contain vowels