Refactor DesignPatterns\Behavioral\Iterator

Behavioral/Iterator/BookListIterator.php

@@ -8,7 +8,7 @@ class BookListIterator implements \Iterator
     /**
      * @var BookList
      */
-    protected $bookList;
+    private $bookList;
 
     /**
      * @var int

Behavioral/Iterator/BookListReverseIterator.php

@@ -2,15 +2,35 @@
 
 namespace DesignPatterns\Behavioral\Iterator;
 
-class BookListReverseIterator extends BookListIterator
+class BookListReverseIterator implements \Iterator
 {
 
+    /**
+     * @var BookList
+     */
+    private $bookList;
+
+    /**
+     * @var int
+     */
+    protected $currentBook = 0;
+
     public function __construct(BookList $bookList)
     {
         $this->bookList = $bookList;
         $this->currentBook = $this->bookList->count() - 1;
     }
 
+    /**
+     * Return the current book
+     * @link http://php.net/manual/en/iterator.current.php
+     * @return Book Can return any type.
+     */
+    public function current()
+    {
+        return $this->bookList->getBook($this->currentBook);
+    }
+
     /**
      * (PHP 5 &gt;= 5.0.0)<br/>
      * Move forward to next element
@@ -21,4 +41,38 @@ class BookListReverseIterator extends BookListIterator
     {
         $this->currentBook--;
     }
+
+    /**
+     * (PHP 5 &gt;= 5.0.0)<br/>
+     * Return the key of the current element
+     * @link http://php.net/manual/en/iterator.key.php
+     * @return mixed scalar on success, or null on failure.
+     */
+    public function key()
+    {
+        return $this->currentBook;
+    }
+
+    /**
+     * (PHP 5 &gt;= 5.0.0)<br/>
+     * Checks if current position is valid
+     * @link http://php.net/manual/en/iterator.valid.php
+     * @return boolean The return value will be casted to boolean and then evaluated.
+     *       Returns true on success or false on failure.
+     */
+    public function valid()
+    {
+        return null !== $this->bookList->getBook($this->currentBook);
+    }
+
+    /**
+     * (PHP 5 &gt;= 5.0.0)<br/>
+     * Rewind the Iterator to the first element
+     * @link http://php.net/manual/en/iterator.rewind.php
+     * @return void Any returned value is ignored.
+     */
+    public function rewind()
+    {
+        $this->currentBook = $this->bookList->count() - 1;
+    }
 }