// Null Node
//
// Douglas Thrift
//
// $Id$

#ifndef _NullNode_hpp_
#define _NullNode_hpp_

#include "Node.hpp"

template <typename Type>
class NullNode : public Node<Type>
{
private:
	bool null;
	NullNode<Type>* next;
	NullNode<Type>* previous;
public:
	NullNode() : null(true) {}
	NullNode(const Type& value) : Node<Type>::Node(value), null(true) {}
	~NullNode() {}
	void addNext(const Type& value);
	void addPrevious(const Type& value);
	void removeNext(void);
	void removePrevious(void);
	void setNext(NullNode<Type>* next) { this->next = next; }
	void setPrevious(NullNode<Type>* previous) { this->previous = previous; }
	NullNode<Type>* getNext(void) const { return next; }
	NullNode<Type>* getPrevious(void) const { return next; }
};

template<typename Type>
void NullNode<Type>::removeNext(void)
{
	NullNode<Type>* behind = next->next;

	delete next;

	next = behind;
}

template<typename Type>
void NullNode<Type>::removePrevious(void)
{
	NullNode<Type>* ahead = previous->previous;

	delete previous;

	previous = ahead;
}

#endif // _NullNode_hpp_