How to match word characters using Java RegEx?

The English alphabet (both cases) and, digits (0 to 9) are considered as word characters. You can match them using the meta character “\w”.

Example 1

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
   public static void main(String args[]) {
      //Reading String from user
      System.out.println("Enter a String");
      Scanner sc = new Scanner(System.in);
      String input = sc.nextLine();
      String regex = "^\\w{5}";
      //Compiling the regular expression
      Pattern pattern = Pattern.compile(regex);
      //Retrieving the matcher object
      Matcher matcher = pattern.matcher(input);
      if(matcher.find()) {
         System.out.println("Match occurred");
      } else {
         System.out.println("Match not occurred");
      }
   }
}

Output 1

Enter a String
hello
Match occurred

Output 2

Enter a String
#how
Match not occurred

Example 2

import java.util.Scanner;
public class RegexExample {
   public static void main( String args[] ) {
      //regular expression to accept word characters
      String regex = "\\w*";
      System.out.println("Enter input value: ");
      Scanner sc = new Scanner(System.in);
      String input = sc.nextLine();
      boolean bool = input.matches(regex);
      if(bool) {
         System.out.println("match occurred");
      } else {
         System.out.println("match not occurred");
      }
   }
}

Output

Enter input value:
*##&
match not occurred