PSR-0 compliance

Observer/User.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace DesignPatterns\Observer;
+
+/**
+ * Observer pattern : The observed object (the subject)
+ * 
+ * The subject maintains a list of Observer and send notificiations.
+ *
+ */
+class User implements \SplSubject
+{
+
+    protected $_data = array();
+
+    /**
+     * @var array
+     */
+    protected $_observers = array();
+
+    /**
+     * attach a new observer
+     *
+     * @param \SplObserver $observer
+     * @return void
+     */
+    public function attach(\SplObserver $observer)
+    {
+        $this->_observers[] = $observer;
+    }
+
+    /**
+     * detach an observer
+     *
+     * @param \SplObserver $observer
+     * @return void
+     */
+    public function detach(\SplObserver $observer)
+    {
+        $index = array_search($observer, $this->_observers);
+
+        if (false !== $index) {
+            unset($this->_observers[$index]);
+        }
+    }
+
+    /**
+     *
+     *
+     * @return void
+     */
+    public function notify()
+    {
+        /** @var SplObserver $observer */
+        foreach ($this->_observers as $observer) {
+            $observer->update($this);
+        }
+    }
+
+    /**
+     * Ideally one would better write setter/getter for all valid attributes and only call notify()
+     * on attributes that matter when changed
+     *
+     * @param $name
+     * @param $value
+     * @return void
+     */
+    public function __set($name, $value)
+    {
+        $this->_data[$name] = $value;
+
+        // notify the observers, that user has been updated
+        $this->notify();
+    }
+
+}
+