Check if the username is valid by using regex

CheckUsername.java

import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
public class UsernameValidator{
 
	  private Pattern pattern;
	  private Matcher matcher;
 
	  private static final String USERNAME_PATTERN = "^[a-z0-9_-]{3,15}$";
 
	  public UsernameValidator(){
		  pattern = Pattern.compile(USERNAME_PATTERN);
	  }
 
	  /**
	   * Validate username with regular expression
	   * @param username username for validation
	   * @return true valid username, false invalid username
	   */
	  public boolean validate(final String username){
 
		  matcher = pattern.matcher(username);
		  return matcher.matches();
 
	  }
}

your validation is good
but i want to add @ # $ & and -