What about if he used public final <T> Set<ConstraintViolation<T>> validate(T object, Class<?>... groups)

This also doesn’t work because it does BeanMetaData<T> rootBeanMetaData = beanMetaDataManager.getBeanMetaData( rootBeanClass );

and then checks to see if the object ArrayList has constraints. It doesn’t so it doesn’t bother checking the items in ArrayList