84 lines
2.3 KiB
C++
84 lines
2.3 KiB
C++
/* This file is part of Mapnik (c++ mapping toolkit)
|
|
* Copyright (C) 2005 Artem Pavlenko
|
|
*
|
|
* Mapnik 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 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.hpp 39 2005-04-10 20:39:53Z pavlenko $
|
|
|
|
#ifndef FACTORY_HPP
|
|
#define FACTORY_HPP
|
|
|
|
#include <stdexcept>
|
|
#include <map>
|
|
#include "utils.hpp"
|
|
|
|
namespace mapnik
|
|
{
|
|
template <typename key_type,
|
|
typename product_type>
|
|
class default_factory_error
|
|
{
|
|
public:
|
|
struct factory_exception : public std::exception
|
|
{
|
|
const char* what() const throw()
|
|
{
|
|
return "uknown object type";
|
|
}
|
|
};
|
|
static product_type* on_unknown_type(const key_type&)
|
|
{
|
|
return 0;
|
|
}
|
|
};
|
|
|
|
template
|
|
<
|
|
typename product_type,
|
|
typename key_type,
|
|
typename product_creator=product_type* (*)(),
|
|
template <typename,typename> class factory_error_policy=default_factory_error
|
|
>
|
|
class factory : public singleton<factory <product_type,key_type,product_creator,factory_error_policy> >,
|
|
factory_error_policy <key_type,product_type>
|
|
{
|
|
private:
|
|
typedef std::map<key_type,product_creator> product_map;
|
|
product_map map_;
|
|
public:
|
|
|
|
bool register_product(const key_type& key,product_creator creator)
|
|
{
|
|
return map_.insert(typename product_map::value_type(key,creator)).second;
|
|
}
|
|
|
|
bool unregister_product(const key_type& key)
|
|
{
|
|
return map_.erase(key)==1;
|
|
}
|
|
|
|
product_type* create_object(const key_type& key,const std::string& file)
|
|
{
|
|
typename product_map::const_iterator pos=map_.find(key);
|
|
if (pos!=map_.end())
|
|
{
|
|
return (pos->second)(file);
|
|
}
|
|
return on_unknown_type(key);
|
|
}
|
|
};
|
|
}
|
|
#endif //FACTORY_HPP
|