Legacy and deprecated functions are here to keep the WC_Abstract_Order clean. This class will be removed in future versions.
Author: WooThemes
Inheritance: extends WC_Data
 /**
  * Get the order if ID is passed, otherwise the order is new and empty.
  * This class should NOT be instantiated, but the get_order function or new WC_Order_Factory.
  * should be used. It is possible, but the aforementioned are preferred and are the only.
  * methods that will be maintained going forward.
  *
  * @param  int|object|WC_Order $read Order to init.
  */
 public function __construct($read = 0)
 {
     parent::__construct($read);
     if (is_numeric($read) && $read > 0) {
         $this->read($read);
     } elseif ($read instanceof self) {
         $this->read(absint($read->get_id()));
     } elseif (!empty($read->ID)) {
         $this->read(absint($read->ID));
     }
     // Set default status if none were read.
     if (!$this->get_status()) {
         $this->set_status(apply_filters('woocommerce_default_order_status', 'pending'));
     }
 }
 /**
  * Get the order if ID is passed, otherwise the order is new and empty.
  * This class should NOT be instantiated, but the get_order function or new WC_Order_Factory.
  * should be used. It is possible, but the aforementioned are preferred and are the only.
  * methods that will be maintained going forward.
  *
  * @param  int|object|WC_Order $order Order to read.
  */
 public function __construct($order = 0)
 {
     parent::__construct($order);
     if (is_numeric($order) && $order > 0) {
         $this->set_id($order);
     } elseif ($order instanceof self) {
         $this->set_id($order->get_id());
     } elseif (!empty($order->ID)) {
         $this->set_id($order->ID);
     } else {
         $this->set_object_read(true);
     }
     // Set default status if none were read.
     if (!$this->get_status()) {
         $this->set_status(apply_filters('woocommerce_default_order_status', 'pending'));
     }
     $this->data_store = WC_Data_Store::load($this->data_store_name);
     if ($this->get_id() > 0) {
         $this->data_store->read($this);
     }
 }