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diff --git a/ACE/examples/Smart_Pointers/Gadget_Part_Impl.h b/ACE/examples/Smart_Pointers/Gadget_Part_Impl.h
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+++ b/ACE/examples/Smart_Pointers/Gadget_Part_Impl.h
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+/* -*- C++ -*- */
+//=============================================================================
+/**
+ *  @file    Gadget_Part_Impl.h
+ *
+ *  $Id$
+ *
+ *  @author Christopher Kohlhoff <chris@kohlhoff.com>
+ */
+//=============================================================================
+
+#ifndef GADGET_PART_IMPL_H
+#define GADGET_PART_IMPL_H
+
+#include "Gadget_Part.h"
+#include "Gadget.h"
+
+/**
+ * @class Gadget_Part_Impl
+ *
+ * @brief An implementation of the Gadget_Part interface.
+ */
+class Gadget_Part_Impl : public Gadget_Part
+{
+public:
+  /// Constructor.
+  Gadget_Part_Impl (Gadget_ptr owner, const char* name, int size);
+
+  /// Destructor.
+  virtual ~Gadget_Part_Impl (void);
+
+  /// Ask the part to print information about itself.
+  virtual void print_info (void);
+
+  /// Ask the part to remove itself from the gadget that contains it.
+  virtual void remove_from_owner (void);
+
+private:
+  /// The gadget that contains this part.
+  ///
+  /// Some things to note about the choice of ACE_Weak_Bound_Ptr (from the
+  /// typedef for Gadget_ptr):
+  /// - We cannot use an ACE_Strong_Bound_Ptr (Gadget_var) since that would
+  ///   result in circular ownership.
+  /// - If we use a raw pointer we have no circular ownership problems, but we
+  ///   are unable to guarantee the lifetime of the owner object for the
+  ///   duration of the remove_from_owner call. This may not be a problem in
+  ///   this limited example, but in multithreaded programs remove_from_owner
+  ///   may be called from a different thread to the thread which manages the
+  ///   owner's lifetime.
+  /// - ACE_Weak_Bound_Ptr (Gadget_ptr) has no ownership semantics, so we have
+  ///   no circular ownership problems. Weak pointers can also be converted
+  ///   back into strong ones, so it is possible to guarantee the lifetime of
+  ///   the owner object for the duration of the remove_from_owner call.
+  Gadget_ptr owner_;
+
+  /// The name of this part.
+  char *name_;
+
+  /// The size of this part.
+  int size_;
+};
+
+#endif /* GADGET_PART_IMPL_H */