protected function load(QueryBuilder $query)
    {
        $metadata = $this->getClassMetadata();
        foreach ($metadata->getFieldMappings() as $field) {
            $fieldtype = $this->getFieldManager()->get($field['fieldtype'], $field);
            if ($fieldtype instanceof FieldTypeInterface) {
                $fieldtype->load($query, $metadata);
            }
        }
    }