protected function doConvertValues($attribute, array $values, $direction, AttributeConverterInterface $converter = null)
{
$converter = is_null($converter) ? $this->getConverterWithOptions($this->schema->getConverter($attribute)) : $converter;
$converter->setAttribute($attribute);
if ($converter->getIsMultiValuedConverter()) {
$values = $converter->{$direction}($values);
} else {
foreach ($values as $index => $value) {
$values[$index] = $converter->{$direction}($value);
}
}
return $values;
}