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diff --git a/TAO/examples/Content_Server/AMI_Observer/Callback_i.h b/TAO/examples/Content_Server/AMI_Observer/Callback_i.h
new file mode 100644
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+++ b/TAO/examples/Content_Server/AMI_Observer/Callback_i.h
@@ -0,0 +1,125 @@
+// -*- C++ -*-
+// $Id$
+
+// ============================================================================
+//
+// = LIBRARY
+//     AMI_Observer
+//
+// = FILENAME
+//     Callback_i.h
+//
+// = DESCRIPTION
+//     Header file for the Web_Server::Callback implementation.
+//
+// = AUTHOR
+//     Ossama Othman <ossama@uci.edu>
+//
+// ============================================================================
+
+#ifndef CALLBACK_I_H
+#define CALLBACK_I_H
+
+#include "ace/FILE_Addr.h"
+#include "ace/FILE_IO.h"
+#include "Push_Web_ServerS.h"
+
+#if !defined (ACE_LACKS_PRAGMA_ONCE)
+# pragma once
+#endif /* ACE_LACKS_PRAGMA_ONCE */
+
+// Implement the Web_Server::Callback interface.
+class Callback_i :
+  public virtual POA_Web_Server::Callback
+{
+  // = TITLE
+  //    Implement the Web_Server::Callback interface.
+  //
+  // = DESCRIPTION
+  //    A <Callback> object implements the Observer pattern.  It
+  //    simply "watches" while the Content Server pushes chunks of
+  //    data to itself.  Once the Content Server pushes the last chunk
+  //    of data, the <Callback> object spawns an external viewer to
+  //    display the pushed data based on the data content type
+  //    returned by the Iterator_Factory::register_callback() method.
+  //
+  //    Since the server pushes data to the <Callback> object
+  //    asynchronously, and since instances of this <Callback> class
+  //    are registered with the Content Server asynchronously, there
+  //    is no guarantee that the metadata containing the content type
+  //    will arrive before the content of the file.  As such, this
+  //    class atomically sets and checks the flags that provide the
+  //    current condition of the metadata and content, in case two
+  //    concurrently running threads attempt to update the state
+  //    contained within a given <Callback> object.
+
+  friend class Callback_i_Friend;
+  // Dummy friend class declaration to quiet down a warning.
+
+public:
+  Callback_i (int *request_count);
+  // Constructor
+
+  virtual void next_chunk (const Web_Server::Chunk_Type &chunk,
+                           CORBA::Boolean last_chunk);
+  // This operation returns the next <chunk> of the file starting at
+  // <offset>.  If there are no more bindings, false is returned.
+
+  void metadata (const Web_Server::Metadata_Type &metadata);
+  // Set metadata associated with received data.
+
+private:
+
+  ~Callback_i (void);
+  // Destructor must be private to ensure that this object is
+  // allocated on the heap.
+
+  int metadata_received (void);
+  // Returns one if the metadata was received, and zero otherwise.
+
+  int content_received (void);
+  // Returns one if the entire content was received, and zero
+  // otherwise.
+
+  int get_viewer (char *viewer, size_t length);
+  // Get the name of the viewer associated with the file being
+  // retrieved.
+
+  int spawn_viewer (void);
+  // Spawn an external view to display the retrieved file.
+
+private:
+
+  void deactivate (void);
+  // Deactivate this Callback servant.
+
+private:
+
+  ACE_FILE_Addr file_;
+  // The Addr corresponding to the retrieved file.
+
+  ACE_FILE_IO file_io_;
+  // The object that provides all file related IO operations
+  // (e.g. read, write, etc).
+
+  Web_Server::AMI_CallbackHandler_var ami_handler_;
+  // Reference to this Reply Handler's self.
+
+  Web_Server::Metadata_Type metadata_;
+  // The metadata associated with the file being retrieved from the
+  // web server.
+
+  int last_chunk_;
+  // Flag that indicates entire data content has been received.
+
+  TAO_SYNCH_MUTEX lock_;
+  // Lock used to prevent race conditions when checking to see if
+  // metadata or entire content has been received.
+
+  int *request_count_;
+  // Pointer to external status monitoring variable. The contents (not
+  // the pointer itself) of the <pending_data> parameter will be
+  // decremented when file retrieval has completed.
+};
+
+#endif  /* CALLBACK_I_H */