start a restructure

Behavioral/Observer/UserObserver.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace DesignPatterns\Observer;
+
+/**
+ * class UserObserver
+ */
+class UserObserver implements \SplObserver
+{
+    /**
+     * This is the only method to implement as an observer.
+     * It is called by the Subject (usually by SplSubject::notify() )
+     * 
+     * @param \SplSubject $subject
+     */
+    public function update(\SplSubject $subject)
+    {
+        echo get_class($subject) . ' has been updated';
+    }
+}