Spring ValidationUtils email Checker

public class DomainValidation implements Validator {
     public boolean supports(Class<?> clazz) {
            return Domain.class.isAssignableFrom(clazz);
     }

     public void validate (Object target , Errors errors ){
                  Domain domain = (Domain) target;
                   ValidationUtils.rejectIfEmptyOrWhitespace(errors, "category", 
                           "required.category","category required !");
                  ValidationUtils.rejectIfEmptyOrWhitespace(errors, "email", 
                           "required.email","Email required !");
                  if (!isValidEmailAddress(board.getEmail())) errors.rejectValue("email",
                                                                   "email.invalid", "Email address is invalid");   

      }

      public boolean isValidEmailAddress(String emailAddress){
        String expression="^[\\w\\-]([\\.\\w])+[\\w]+@([\\w\\-]+\\.)+
                                  [A-Z]{2,4}$";
        CharSequence inputStr = emailAddress;
        Pattern pattern = Pattern.compile(expression,Pattern.CASE_INSENSITIVE);
        Matcher matcher = pattern.matcher(inputStr);
        return matcher.matches();
    } 



}