medical image analysis SVN (old)

/* -*- mona-c++  -*-
 * Copyright (c) Leipzig, Madrid 2004 - 2008 
 * Max-Planck-Institute for Human Cognitive and Brain Science	
 * Max-Planck-Institute for Evolutionary Anthropology 
 * BIT, ETSI Telecomunicacion, UPM
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

// $Id: factory.hh,v 1.4 2005/06/03 11:00:38 gerddie Exp $

/** 
    \author: Gert Wollny < wollny at cbs mpg de >
    implements a plugin loading factory
*/

#ifndef FACTORY_HH
#define FACTORY_HH

#include <iostream>
#include <memory>
#include <boost/shared_ptr.hpp>

#include <libmona/plugin_handler.hh>
#include <libmona/monaPlugIns.hh>
#include <libmona/command_parser.hh>

MONA_NAMESPACE_BEGIN

/** this is a producer class, that creates objects based 
    on a prototype. The Prototy class must provide a function "clone", 
    that returns a copy of the prototype. */

template <typename Prototype>
class TProtoFactory {
public: 
	/** Constructor to create the Factory, and initialise it with a prototype */ 
	TProtoFactory(const Prototype *prototype); 

	/** reset the factory to e new prototype */
	void reset(const Prototype *prototype); 

	/** Produce a copy of the prototype */ 
	Prototype *produce() const; 
private: 
	std::auto_ptr<const Prototype> _M_prototype;
};


/** this is the class to load a certain plugin */
template <class T>
class TFactory: public CPluginBase {
public: 
	typedef T Product; 
	typedef boost::shared_ptr<T> ProductPtr; 
	
	/** initialise the plugin by the names 
	    \remark what are these names and types good for?
	*/
	TFactory(char const * const  name, char const * const  type, char const * const  data);
	
	/** the creation function 
	    \params options the options to initialise the plugin 
	    \returns an instance of the requested object
	*/
	virtual ProductPtr create(const CParsedOptions& options) const = 0;
	
	/** this is the important part  of the plugin loading mechanism:
	    \param params is a string that describes the options for loading the plugin
	    \param ph is the handler of a certain kind of plugins 
	    \returns a entitity of the requested functionallity 
	*/
	
	template <class  PluginHandler>
	static ProductPtr produce(char const *params, const PluginHandler& ph)
	{
		CComplexOptionParser param_list(params);
		
		if (param_list.size() < 1) 
			return ProductPtr(); 
		
		const std::string& factory_name = param_list.begin()->first; 
		
		if (factory_name == plugin_help) {
			ph.print_help();
			return ProductPtr(); 
		}
		
		const typename PluginHandler::HandledPluginType *factory = ph.find_plugin_by_name(factory_name.c_str());
		if (factory)
			return factory->create(param_list.begin()->second);
		else 
			return ProductPtr(); 
	}
	
	/**
	   Just ensure a virtual destructor
	 */
	virtual ~TFactory(); 
};

template <typename Prototype>
TProtoFactory<Prototype>::TProtoFactory(const Prototype *prototype): 
	_M_prototype(prototype)
{
}

template <typename Prototype>
void TProtoFactory<Prototype>::reset(const Prototype *prototype)
{
	_M_prototype.reset(prototype);
}

template <typename Prototype>
Prototype *TProtoFactory<Prototype>::produce()const
{
	if (_M_prototype.get())
		return _M_prototype->clone(); 
	else 
		return NULL; 
}

template <class T>
TFactory<T>::TFactory(char const * const  name, char const * const  type, char const * const  data):
	CPluginBase(name, type, data)
{
}

template <class T>
TFactory<T>::~TFactory()
{
}

MONA_NAMESPACE_END   
#endif

/*
  $Log: factory.hh,v $
  Revision 1.4  2005/06/03 11:00:38  gerddie
  add log entries to all files

*/