observer.h

来自「在LINUX下运行的仿真机器人服务器源代码」· C头文件 代码 · 共 131 行

// -*-c++-*-

/***************************************************************************
                                observer.h 
                           Base for observer classes
                             -------------------
    begin                : 2002-10-07
    copyright            : (C) 2002 by The RoboCup Soccer Simulator 
                           Maintenance Group.
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU LGPL as published by the Free Software  *
 *   Foundation; either version 2 of the License, or (at your option) any  *
 *   later version.                                                        *
 *                                                                         *
 ***************************************************************************/


#ifndef RCSSOBSERVER_H
#define RCSSOBSERVER_H

#include "rcssexceptions.h"
#include <memory>

namespace rcss
{

/*!
//===================================================================
//
//  CLASS: Observer
//
//  DESC: Base observer.
//
//===================================================================
*/

    template < class S >
    class BaseObserver
    {
    public:
        typedef S Sender;
    private:
        Sender* M_sender;
        bool M_owns_sender;

    protected:
//          std::ostream& 
//          transport()
//          { return M_transport; }

    public:
        BaseObserver()
            : M_sender( NULL ),
              M_owns_sender( false )
        {}

        BaseObserver( Sender& sender )
            : M_sender( &sender ),
              M_owns_sender( false )
        {}

        BaseObserver( std::auto_ptr< Sender > sender )
            : M_sender( sender.release() ),
              M_owns_sender( true )
        {}


        ~BaseObserver()
        {
            clear();
        }

        void
        setSender( Sender& sender )
        {
            clear();
            M_sender = &sender;
            M_owns_sender = false;
        }

        void
        setSender( std::auto_ptr< Sender > sender )
        {
            clear();
            M_sender = sender.release();
            M_owns_sender = true;
        }

        Sender&
        sender()
        { 
            if( M_sender == NULL )
                throw util::NullErr( __FILE__, __LINE__,
                                     "Sender is null" );
            return *M_sender; 
        }

        const Sender&
        sender() const
        { 
            if( M_sender == NULL )
                throw util::NullErr( __FILE__, __LINE__,
                                     "Sender is null" );
            return *M_sender;
        }

    private:
        void
        clear()
        {
            if( M_owns_sender )
            {
                delete M_sender;
                M_sender = NULL;
            }
        }

        BaseObserver( const BaseObserver& ); // not used;
        
        BaseObserver&
        operator=( const BaseObserver& ); // not used;
    };
}

#endif