public void updateCredential(RealmModel realm, UserModel user, UserCredentialModel credential) {
   if (credential.getType().equals(UserCredentialModel.PASSWORD)) {
     if (realm.getPasswordPolicy() != null) {
       PasswordPolicy.Error error =
           realm.getPasswordPolicy().validate(user, credential.getValue());
       if (error != null) throw new ModelException(error.getMessage(), error.getParameters());
     }
   }
   user.updateCredential(credential);
 }