javax.validator with spring component

Question

I use javax.validation with Spring. In my test (groovy) I explicitly create validator.

import javax.validation.Validation
import javax.validation.Validator
import javax.validation.ValidatorFactory

ValidatorFactory factory = Validation.buildDefaultValidatorFactory()
Validator validator = factory.getValidator()

when:
Set<ConstraintViolation<User>> constraints = validator.validate(entity)

My validator in java

public class EntityDynamicValidator implements ConstraintValidator<SomeConstraint, Entity> {

    private GroupService groupService;

    // This constructor is required, see the link bellow.
    public UserDynamicEnumValidator() {
    }

    public UserDynamicEnumValidator(final GroupService groupService) {
        this.groupService = groupService;
    }

    @Override
    public boolean isValid(final Entity entity, final ConstraintValidatorContext context) {
        Something something = groupService.findByValue(entity.getValue());
        // Validate all this stuff
    }
}

I need to pass a Spring service to the validator.

I have a default constructor because there is an issue Spring unit test issue with Validator

Answer 1

I also tried to solve this, however the tests are fully low level unit tests on my side and I wanted to avoid too much of a context. I couldn't even use your approach. The solution my side was to add a custom ConstraintValidatorBean into the mockmvc. That custom implementation could get a list of validator class Class objects and so if the factory tried to create a validator, I returned a Mockito.mock version of it instead of the real one and I could also look that up for expectation settings.

Answer 2

Feel free to share your knowledge. This is how I solved this task.

I created a Spring component and it has a static field (GroupService which is initialized in constructor).

@Component // Spring component.
class ServiceHolderComponent {

    private static GroupService GROUP_SERVICE;

    @Autowired4
    public ServiceHolderComponent(final GroupService groupService) {
        GROUP_SERVICE = Validate.notNull(groupService); //apache lib
    }

    public static GroupService getGroupService() {
        return GROUP_SERVICE;
    }
}

And now validator with default constructor.

public class EntityDynamicValidator implements ConstraintValidator<SomeConstraint, Entity> {

    private GroupService groupService;

    public UserDynamicEnumValidator() {
        this(ServiceHolderComponent.getGroupService());
    }

    public UserDynamicEnumValidator(final GroupService groupService) {
        this.groupService = groupService;
    }

    @Override
    public boolean isValid(final Entity entity, final ConstraintValidatorContext context) {
        Something something = groupService.findByValue(entity.getValue());
        // Validate all this stuff
    }
}