DInstance.hpp

/*
 * Copyright (c) 2011-2016, Matthieu FAESSEL and ARMINES
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of Matthieu FAESSEL, or ARMINES nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
 
#ifndef _D_INSTANCE_HPP
#define _D_INSTANCE_HPP
 
#include <iostream>
#include "Core/include/DErrors.h"
 
namespace smil
{
  template <typename T>
  class UniqueInstance
  {
  protected:
    UniqueInstance()
    {
 
    }
 
    virtual ~UniqueInstance()
    {
    }
 
  public:
    static T *getInstance()
    {
      T::initialize();
      return (static_cast<T *>(T::_instance));
    }
 
    // Can be overloaded because of the T::initialize call
    static RES_T initialize()
    {
      if (T::_instance == NULL)
        T::_instance = new T();
      return RES_OK;
    }
 
    static void kill()
    {
      if (T::_instance) {
        delete T::_instance;
        T::_instance = NULL;
      }
    }
 
  protected:
    // Unique instance
    static T *_instance;
 
  };
 
  template <typename T>
  T *UniqueInstance<T>::_instance = NULL;
 
} // namespace smil
 
#endif // _D_INSTANCE_HPP