iterator.h

来自「详细介绍了20种设计模式的具体实现框架,很有参考价值」· C头文件 代码 · 共 78 行

/********************************************************************
	created:	2006/08/04
	filename: 	Iterator.h
	author:		李创
                http://www.cppblog.com/converse/

	purpose:	Iterator模式的演示代码
*********************************************************************/

#ifndef ITERATOR_H
#define ITERATOR_H

typedef int DATA;

class Iterater;

// 容器的抽象基类
class Aggregate
{
public:
	virtual ~Aggregate(){}

	virtual Iterater* CreateIterater(Aggregate *pAggregate) = 0;
	virtual int GetSize() = 0;
	virtual DATA GetItem(int nIndex) = 0;
};

// 迭代器的抽象基类
class Iterater
{
public:
	virtual ~Iterater(){}

	virtual void First()		= 0;
	virtual void Next()			= 0;
	virtual bool IsDone()		= 0;
	virtual DATA CurrentItem()	= 0;

private:
};

// 一个具体的容器类,这里是用数组表示
class ConcreateAggregate
	: public Aggregate
{
public:
	ConcreateAggregate(int nSize);
	virtual ~ConcreateAggregate();

	virtual Iterater* CreateIterater(Aggregate *pAggregate);
	virtual int GetSize();
	virtual DATA GetItem(int nIndex);

private:
	int m_nSize;
	DATA *m_pData;
};

// 访问ConcreateAggregate容器类的迭代器类
class ConcreateIterater
	: public Iterater
{
public:
	ConcreateIterater(Aggregate* pAggregate);
	virtual ~ConcreateIterater(){}

	virtual void First();
	virtual void Next();
	virtual bool IsDone();
	virtual DATA CurrentItem();

private:
	Aggregate  *m_pConcreateAggregate;
	int			m_nIndex;
};

#endif