名字和姓氏设置为NULL - Magento 2

is there a way to get, what class call a Particular Observer?

I have this Observer,

public function execute(
\Magento\Framework\Event\Observer $observer
) {
    $customer = $observer->getEvent()->getData();
    $eventName = $observer->getEvent()->getName();
    $name= $customer->getFirstname();
    $lastname = $customer->getLastName();
    $now = date(‘Y-m-d H:i:s’);
    $this->logger->info($now.'CUSTOMER_SAVE_BEFORE____________’);
    $this->logger->info("Event Name: ".$eventName);
    $this->logger->info('Name: ', $name);
    $this->logger->info('Lastname: ', $lastname);
    $this->logger->info($now.’______________________________________________________________’);

}

I need to log, What class Call this Observer, I have an issue on a Magento 2.2.4 Project. Sometimes First Name and Last Name of logged customers are set to NULL, I'm going crazy to understand what is causing this issue...

Thanks Leonardo

Replace your code with below code

public function execute(
\Magento\Framework\Event\Observer $observer
) {
    $customer  = $observer->getCustomer();
    $eventName = $observer->getEvent()->getName();
    $name      = $customer->getFirstname();
    $lastname  = $customer->getLastName();
    $now       = date(‘Y-m-d H:i:s’);
    $this->logger->info($now.'CUSTOMER_SAVE_BEFORE____________’);
    $this->logger->info("Event Name: ".$eventName);
    $this->logger->info('Name: ', $name);
    $this->logger->info('Lastname: ', $lastname);
    $this->logger->info($now.’______________________________________________________________’);

}

I hope it will help..!!