Connector/CleanupService/CleanupService.php
private function collectObjectIdentifiers(Definition $definition)
    {
        $this->outputHandler->writeLine(sprintf(
            'checking transfer objects for existence: Type: %s, %s -> %s',
            $definition->getObjectType(),
            $definition->getOriginAdapterName(),
            $definition->getDestinationAdapterName()
        ));

        /**
         * @var TransferObjectInterface[] $objects
         */
        $objects = $this->serviceBus->handle($this->queryFactory->create(
            $definition->getOriginAdapterName(),
            $definition->getObjectType(),
            QueryType::ALL
        ));

        $found = false;

        if (empty($objects)) {
            return false;
        }

        foreach ($objects as $transferObject) {
            if (false === $found) {
                $found = true;
            }

            $this->elements[] = [
                'objectIdentifier' => $transferObject->getIdentifier(),
                'adapterName' => $definition->getDestinationAdapterName(),
                'type' => $transferObject->getType(),
            ];
        }

        return !(false === $found);
    }
private function collectObjectIdentifiers(Definition $definition)
    {
        $this->outputHandler->writeLine(sprintf(
            'checking transfer objects for existence: Type: %s, %s -> %s',
            $definition->getObjectType(),
            $definition->getOriginAdapterName(),
            $definition->getDestinationAdapterName()
        ));

        /**
         * @var TransferObjectInterface[] $objects
         */
        $objects = $this->serviceBus->handle($this->queryFactory->create(
            $definition->getOriginAdapterName(),
            $definition->getObjectType(),
            QueryType::ALL
        ));

        $found = false;

        if (empty($objects)) {
            return false;
        }

        foreach ($objects as $transferObject) {
            if (false === $found) {
                $found = true;
            }

            $this->elements[] = [
                'objectIdentifier' => $transferObject->getIdentifier(),
                'adapterName' => $definition->getDestinationAdapterName(),
                'type' => $transferObject->getType(),
            ];
        }

        return !(false === $found);
    }
@param Definition $definition

@return bool