CeylanGenericMVCDefines.h

Go to the documentation of this file.

/* 
 * Copyright (C) 2003-2009 Olivier Boudeville
 *
 * This file is part of the Ceylan library.
 *
 * The Ceylan library is free software: you can redistribute it and/or modify
 * it under the terms of either the GNU Lesser General Public License or
 * the GNU General Public License, as they are published by the Free Software
 * Foundation, either version 3 of these Licenses, or (at your option) 
 * any later version.
 *
 * The Ceylan library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License and the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License and the GNU General Public License along with the Ceylan library.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * Author: Olivier Boudeville (olivier.boudeville@esperide.com)
 *
 */


#ifndef CEYLAN_GENERIC_MVC_DEFINES_H_
#define CEYLAN_GENERIC_MVC_DEFINES_H_


#include "CeylanException.h"  // for inheritance


#include <string>



/*
 * @note In most cases, this generic (template-based) MVC version should be
 * preferred to the event-based MVC one (ex: based on Ceylan::MVC::Model).
 *
 */


/*
 * With the MVC framework, we have Controller -> Model -> View, with '->'
 * meaning "depending on".
 *
 * In terms of life-cycle management, having a model know all its
 * MVC-related components (views and controllers) is more convenient, as 
 * when the model determines it should be deallocated, it can manage
 * automatically its related objects (i.e. deallocate its views and 
 * controllers).
 *
 * All references detained by a MVC instance to other instances should be
 * 'const': if A -> B, then A will not post updates to B, on the contrary B
 * will pick information from A, thus A may reference B just for life-cycle
 * reasons ('const' will suffice), and B will only call 'const' methods of A
 * to get the informations it needs (hence 'const' should suffice again).
 *
 * Therefore A may only reference a generic mother class of B (as A
 * will not act on it, only maybe have to deallocate it), whereas B needs
 * to know the actual (specialized) class of A, since it will have to call
 * (const) methods of it.
 *
 */
 
  
/*
 * Note that, at this level of abstraction, a MVC class does not have to know 
 * the specific class(es) it depends on (ex: a SingleViewGenericModel just
 * need a BaseView pointer, regardless of the actual view class).
 *
 * However, the point is that, as soon as these mother classes are subclassed, 
 * these actual subclasses will need to know the specific class they 
 * depend on, as they intend to call their class-specific methods.
 * Hence for example a SingleViewGenericModel would need to rely on a 
 * referencee to MySpecificView, rather than on a mere BaseView.
 *
 * Therefore, as soon as a MVC class can have a reference on another, we
 * indeed need to define a templated version of it, so that we keep the
 * actual type (class) of referenced instances.
 *
 */



// Allows to avoid complex header dependencies.


namespace Ceylan
{


    namespace MVC
    {
    
    
        class GenericMVCException : public Ceylan::Exception
        {
    
            public:
    
    
                GenericMVCException( const std::string & message ) :
                    Ceylan::Exception( message )
                {
    
                }
    
    
                virtual ~GenericMVCException() throw()
                {
    
                }
    
        } ;
    
    
    }

    
}   



#endif // CEYLAN_GENERIC_MVC_DEFINES_H_

---