Neos\Flow\Persistence\Doctrine\Mapping\Driver\FlowAnnotationDriver::evaluateJoinColumnAnnotations PHP Method

    protected function evaluateJoinColumnAnnotations(\ReflectionProperty $property)
    {
        $joinColumns = [];
        /** @var ORM\JoinColumn $joinColumnAnnotation */
        if ($joinColumnAnnotation = $this->reader->getPropertyAnnotation($property, ORM\JoinColumn::class)) {
            $joinColumns[] = $this->joinColumnToArray($joinColumnAnnotation, strtolower($property->getName()));
        } elseif ($joinColumnsAnnotation = $this->reader->getPropertyAnnotation($property, ORM\JoinColumns::class)) {
            foreach ($joinColumnsAnnotation->value as $joinColumnAnnotation) {
                $joinColumns[] = $this->joinColumnToArray($joinColumnAnnotation, strtolower($property->getName()));
            }
        }
        return $joinColumns;
    }