PHP7 Observer

Behavioral/Observer/User.php

@@ -3,60 +3,42 @@
 namespace DesignPatterns\Behavioral\Observer;
 
 /**
- * Observer pattern : The observed object (the subject).
- *
- * The subject maintains a list of Observers and sends notifications.
+ * User implements the observed object (called Subject), it maintains a list of observers and sends notifications to
+ * them in case changes are made on the User object
  */
 class User implements \SplSubject
 {
     /**
-     * user data.
-     *
-     * @var array
+     * @var string
      */
-    protected $data = array();
+    private $email;
 
     /**
-     * observers.
-     *
      * @var \SplObjectStorage
      */
-    protected $observers;
+    private $observers;
 
     public function __construct()
     {
         $this->observers = new \SplObjectStorage();
     }
 
-    /**
-     * attach a new observer.
-     *
-     * @param \SplObserver $observer
-     *
-     * @return void
-     */
     public function attach(\SplObserver $observer)
     {
         $this->observers->attach($observer);
     }
 
-    /**
-     * detach an observer.
-     *
-     * @param \SplObserver $observer
-     *
-     * @return void
-     */
     public function detach(\SplObserver $observer)
     {
         $this->observers->detach($observer);
     }
 
-    /**
-     * notify observers.
-     *
-     * @return void
-     */
+    public function changeEmail(string $email)
+    {
+        $this->email = $email;
+        $this->notify();
+    }
+
     public function notify()
     {
         /** @var \SplObserver $observer */
@@ -64,21 +46,4 @@ class User implements \SplSubject
             $observer->update($this);
         }
     }
-
-    /**
-     * Ideally one would better write setter/getter for all valid attributes and only call notify()
-     * on attributes that matter when changed.
-     *
-     * @param string $name
-     * @param mixed  $value
-     *
-     * @return void
-     */
-    public function __set($name, $value)
-    {
-        $this->data[$name] = $value;
-
-        // notify the observers, that user has been updated
-        $this->notify();
-    }
 }