Program to match vowels in a string using regular expression in Java

You can group all the required characters to match within the square braces “[ ]” i.e. The metacharacter/sub-expression “[ ]” matches all the specified characters. Therefore, to match all the letters specify the vowel letters within these as shown below −

[aeiouAEIOU]

Example 1

import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class MatchVowels {    public static void main( String args[] ) {       String regex = "[aeiouAEIOU]";       System.out.println("Enter input string: ");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       //Compiling the regular expression       Pattern.compile(regex);       //Compiling the regular expression       Pattern pattern = Pattern.compile(regex);       Matcher matcher = pattern.matcher(input);       if(matcher.find()) {          System.out.println("The input string contains vowels");       } else {          System.out.println("The input string does not contain vowels");       }    } }

Output

Enter input string: hello how are you welcome The input string contains vowels

Example 2

import java.util.Scanner; public class Test {    public static void main( String args[] ) {       String regex = "[aeiouAEIOU]";       System.out.println("Enter input string: ");       Scanner sc = new Scanner(System.in);       String input = sc.nextLine();       boolean result = input.matches(regex);       if(result) {          System.out.println("The input string contains vowels");       } else {          System.out.println("The input string does not contain vowels");       }    } }

Output

Enter input string: hello how are you welcome The input string does not contain vowels