Run Validation before #HandleBeforeCreate - spring

Question

I'm having some problem with validation with Spring Rest, the #HandleBeforeCreate event handler is running before the validation. I was expecting it to run after the validation.
In my test application I have a transaction, which has two fields to store the transaction value, one for the real transaction currency and another for the final value converted to the user currency. In my handle before create I'm dealing with that conversion, but I want the request to stop in the validator if the amount is null.
I could validate the resource in the event handler (I'm ready to handle a RepositoryConstraintViolationException), but it make me think on the point of using validator. It also seams a little inefficient that on every data rest request, spring loop through all validator checking if they support the object class.
Is validation on EventHandlers preferable than Validators (for performance reasons)? How can I force validator to run before EventHandlers?
*I'm using spring-boot 1.4.2.RELEASE
Validator
public class TransactionValidator extends SpringValidator<Transaction> {
#Override
public boolean supports(Class<?> clazz) {
return Transaction.class.equals(clazz) ;
}
#Override
public void validateObject(Transaction transaction, Errors errors) {
... validations ...
}
}
public abstract class SpringValidator<T> implements Validator {
#Override
public void validate(Object target, Errors errors) {
validateObject((T) target, errors);
}
protected abstract void validateObject(T target, Errors errors);
}
Event Handler
#Component
#RequiredArgsConstructor
#RepositoryEventHandler(Transaction.class)
public class TransacationEventHandler {
private final CurrencyUnitService currencyUnitService;
#HandleBeforeCreate
public void beforeCreate(Transaction transaction) {
adjustTransactionAmount(transaction);
}
#HandleBeforeSave
public void beforeSave(Transaction transaction) {
adjustTransactionAmount(transaction);
}
}
Edit
I checked the source code and the listeners are invoked in the following order:
Which make sense actually, using a BeforeCreateHandler is the only way to fix/change something in the Entity before running the Validator. I'm 100% open to inputs.

Answer 1

1. Use #Validated (did not test it)
You could do this:
#HandleBeforeCreate
public void beforeCreate(#Validated Transaction transaction) {
adjustTransactionAmount(transaction);
}
2. Otherwise - you may define the Validator through Java Configuration
You may follow this answer from #MathiasDpunkt (Spring data rest validation + exception mapper: confusing):
#Configuration
public class MyValidationConfiguration extends RepositoryRestConfigurerAdapter {
#Bean
#Primary
/**
* Create a validator to use in bean validation - primary to be able to autowire without qualifier
*/
Validator validator() {
return new LocalValidatorFactoryBean();
}
#Override
public void configureValidatingRepositoryEventListener(ValidatingRepositoryEventListener
validatingListener) {
Validator validator = validator();
//bean validation always before save and create
validatingListener.addValidator("beforeCreate", validator);
validatingListener.addValidator("beforeSave", validator);
}
}