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diff --git a/trunk/ACE/examples/Smart_Pointers/Widget_Impl.h b/trunk/ACE/examples/Smart_Pointers/Widget_Impl.h
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+++ b/trunk/ACE/examples/Smart_Pointers/Widget_Impl.h
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+// -*- C++ -*-
+
+//=============================================================================
+/**
+ *  @file    Widget_Impl.h
+ *
+ *  $Id$
+ *
+ *  @author Christopher Kohlhoff <chris@kohlhoff.com>
+ */
+//=============================================================================
+
+#ifndef WIDGET_IMPL_H
+#define WIDGET_IMPL_H
+
+#include "Widget.h"
+#include "Widget_Part.h"
+
+#include "ace/Unbounded_Queue.h"
+#include "ace/Refcounted_Auto_Ptr.h"
+#include "ace/Synch_Traits.h"
+#include "ace/Thread_Mutex.h"
+
+/**
+ * @class Widget_Impl
+ *
+ * @brief An implementation of the Widget interface.
+ */
+class Widget_Impl : public Widget
+{
+public:
+  /// Constructor.
+  Widget_Impl (void);
+
+  /// Destructor.
+  virtual ~Widget_Impl (void);
+
+  /// Add a new part to the widget. The widget takes ownership of the part
+  /// object.
+  virtual void add_part (Widget_Part *part);
+
+  /// Remove a random part from the widget. Ownership of the part is returned
+  /// to the caller.
+  virtual Widget_Part *remove_part (void);
+
+  /// Ask the widget to print information about the parts that it contains.
+  virtual void list_parts (void);
+
+private:
+  /// The parts which make up this widget. The set actually contains instances
+  /// of ACE_Refcounted_Auto_Ptr to automatically manage the lifetimes of the
+  /// constituent parts.
+  ///
+  /// Some things to note about the choice of ACE_Refcounted_Auto_Ptr:
+  /// - We cannot use auto_ptr to manage the objects, since auto_ptr does not
+  ///   support the copying and assignment semantics necessary for storage in
+  ///   a container.
+  /// - The ACE_Strong_Bound_Ptr reference counted pointer could be used to
+  ///   store objects in a container, however (for reasons of safety) it
+  ///   provides no way to release ownership of the object from the smart
+  ///   pointer. We need to be able to release ownership to implement the
+  ///   remove_part method.
+  /// - ACE_Refcounted_Ptr can both be stored in containers and allows us to
+  ///   release ownership of the pointer that it contains.
+  ACE_Unbounded_Queue<ACE_Refcounted_Auto_Ptr<Widget_Part, ACE_SYNCH_MUTEX> > parts_;
+};
+
+#endif /* WIDGET_IMPL_H */