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/* ScummVM Tools
*
* ScummVM Tools is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef DEC_OBJECTFACTORY_H
#define DEC_OBJECTFACTORY_H
#include <map>
#include <string>
#include "common/scummsys.h"
/**
* Template function for creating an instance of Type.
*/
template<typename BaseType, typename Type>
BaseType *createObject() {
return new Type();
}
/**
* Generic factory for a class and its subclasses.
*/
template<typename KeyType, typename BaseType>
class ObjectFactory {
private:
/**
* Function pointer to the object creation function.
*/
typedef BaseType *(*CreateFunc)();
/**
* Type used to store registered entries.
*/
typedef std::map<KeyType, CreateFunc> RegistryMap;
RegistryMap _registry; ///< Map from an identifier to a creation function.
public:
/**
* Register a new entry.
*
* @param key The key to register the class under.
*/
template<typename Type>
void addEntry(const KeyType &key) {
_registry[key] = &createObject<BaseType, Type>;
}
/**
* Creates an instance of some registered class.
*
* @param key The key associated with the desired class.
* @return NULL if the name is not registered, else an instance of the associated class.
*/
BaseType *create(const KeyType &key) const {
typename RegistryMap::const_iterator entry = _registry.find(key);
if (entry == _registry.end())
return NULL;
return (entry->second)();
}
};
#endif
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