### Question:
EmailProvider implements NotificationProvider { public Boolean isEmailValid(Email toEmail) { if (toEmail == null) return false; return isEmailValid(toEmail.getEmail()); } @Inject  EmailProvider(@Named("email.provider.apikey") String sendGridApiKey, PersonDAO personDao, PlaceDAO placeDao, AccountDAO accountDao, NotificationMessageRenderer messageRenderer, UpstreamNotificationResponder responder); @Override void notifyCustomer(Notification notification); Boolean isEmailValid(Email toEmail); Boolean isEmailValid(String email); void sendEmail(MailParams mailParams);  }### Answer:
@Test public void testEmailValidation() { Boolean result = uut.isEmailValid((Email) null); assertFalse(result); result = uut.isEmailValid(""); assertFalse(result); result = uut.isEmailValid((String) null); assertFalse(result); result = uut.isEmailValid("not valid email"); assertFalse(result); result = uut.isEmailValid("wes.stueve@wds-it.com"); assertTrue(result); }