Hibernate validation - autowired returns null - spring

Question

After looking around, I couldn't find any good solution to this.
My autowired didn't work as expected where it returns null. I've autowired this particular class in other classes and it works so it only doesn't work in constraintvalidator classes.
UserService class
#Service
public class UserService {
#Autowired
private UserRepository userRep;
public void addUser(User user) {
userRep.save(user);
}
public void deleteUser(long userId) {
userRep.deleteById(userId);
}
public List<User> retrieveAllUsers(){
Iterable<User>temp =userRep.findAll();
List<User>allUsers = null;
temp.forEach(allUsers::add);
return allUsers;
}
public boolean searchByEmail(String email) {
return userRep.findByEmail(email);
}
public void updateUser(User user) {
userRep.save(user);
}
}
Annotation interface class
#Target(ElementType.FIELD)
//When will the annotation be processed compilation, runtime etc
#Retention(RetentionPolicy.RUNTIME)
//Where is the logic
#Constraint(validatedBy = EmailValidator.class)
#Documented
public #interface ValidEmail {
//Error message
String message() default "Invalid email";
//Required for annotation
Class<?>[] groups() default {};
Class<? extends Payload>[] payload() default {};
}
Annotation logic class. The autowired here returns null
public class EmailValidator implements ConstraintValidator<ValidEmail, String> {
#Autowired
private UserService service;
//Actual place to place the logic to check if the data is valid or not
#Override
public boolean isValid(String email, ConstraintValidatorContext context) {
if (email == null) {
return false;
}
List<User> users = service.retrieveAllUsers();
if (users.size() > 0) {
return Pattern.matches("(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9]))\\.){3}(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9])|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])", email)
&& service.searchByEmail(email);
}
else {
return Pattern.matches("(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9]))\\.){3}(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9])|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])", email);
}
}
#Override
public void initialize(ValidEmail validEmail) {
validEmail.message();
}
}
Main
#SpringBootApplication
#ComponentScan(basePackages = {
"com.Alex.Mains", "com.Alex.UserPackage", "com.Alex.Flights", "com.Alex.Security"
})
#EntityScan( basePackages = {"com.Alex.UserPackage", "com.Alex.Flights"})
#EnableJpaRepositories({"com.Alex.UserPackage", "com.Alex.Flights"})
public class JpaApplication {
public static void main(String[] args) {
SpringApplication.run(JpaApplication.class, args);
}
// #Bean
// public Validator validator(final AutowireCapableBeanFactory beanFactory) {
//
// ValidatorFactory validatorFactory = Validation.byProvider(HibernateValidator.class)
// .configure()
// .constraintValidatorFactory(new SpringConstraintValidatorFactory(beanFactory))
// .buildValidatorFactory();
//
// return validatorFactory.getValidator();
// }
}
Edit: Tried #Componenet

Answer 1

Fixed with adding the following to application.properties. No idea why but it works
spring.jpa.properties.javax.persistence.validation.mode=none

Answer 2

EDIT: My Suggestion
Instead of a custom validator, use the existing #EMail and a unique constraint:
#Entity
public class User {
// ...your properties
#Email
#Column(unique = true)
private String email.
// Rest of class...
}
OLD:
So, first off:
List<User> users = service.retrieveAllUsers();
if (users.size() > 0) {
You are fetching all the Users from the database, just to check whether any users exists? This is very, very inefficient. If you are already using Spring Data, you can just do
#Query("SELECT COUNT(*) > 0 FROM Users")
boolean anyExists();
Furthermore, your Service does not get injected, because EmailValidator is a POJO (plain old java object) and not a Spring managed component. If you annotate it with #Component or #Service Spring will take care of injection.
But I would not recommend that. I'm not sure what your exact use case is, but validators are often used on Entities and as such, they get called when the entity is created or updated. You don't want to issue additional queries in those cases.
Like I said, I don't know what exactly you are trying to achieve, but you could use the existing #Email validator (you can even provide a custom regular expression with the regexp attribute).