@Configuration
public class AppConfig {

    @Bean
    public JaxbAnnotationModule jaxbAnnotationModule() {
        return new JaxbAnnotationModule();
    }

    @Bean
    public ObjectMapper objectMapper() {
        ObjectMapper mapper = new ObjectMapper();
        mapper.registerModule(new JaxbAnnotationModule());
        mapper.setAnnotationIntrospector(new JaxbAnnotationIntrospector(mapper.getTypeFactory()));
        mapper.setSerializationInclusion(Include.NON_NULL);
        return mapper;
    }
}

@Autowired
private Validator validator;
...Some code...
Set<ConstraintViolation<Request>> violations = validator.validate(request);