How to remove vowels from a string using regular expressions in Java?

The simple character class “[ ]” matches all the specified characters in it. The following expression matches the characters except for xyz.

"[xyz]"

Similarly, the following expression matches all the vowels in the given input string.

"([^aeiouAEIOU0-9\\W]+)";

Then you can remove the matched characters by replacing them with the empty string “”, using the replaceAll() method.

Example 1

public class RemovingVowels {
   public static void main( String args[] ) {
      String input = "Hi welcome to tutorialspoint";
      String regex = "[aeiouAEIOU]";
      String result = input.replaceAll(regex, "");
      System.out.println("Result: "+result);
   }
}

Output

Result: H wlcm t ttrlspnt

Example 2

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Test {
   public static void main( String args[] ) {
      Scanner sc = new Scanner(System.in);
      System.out.println("Enter input string: ");
      String input = sc.nextLine();
      String regex = "[aeiouAEIOU]";
      String constants = "";
      System.out.println("Input string: \n"+input);
      //Creating a pattern object
      Pattern pattern = Pattern.compile(regex);
      //Matching the compiled pattern in the String
      Matcher matcher = pattern.matcher(input);
      //Creating an empty string buffer
      StringBuffer sb = new StringBuffer();
      while (matcher.find()) {
         constants = constants+matcher.group();
         matcher.appendReplacement(sb, "");
      }
      matcher.appendTail(sb);
      System.out.println("Result: \n"+ sb.toString()+constants );
   }
}

Output

Enter input string:
this is a sample text
Input string:
this is a sample text
Result:
ths s smpl txtiiaaee