//-----------------------------------------------------------------------------+
// Copyright (C), 1998-2007, Beijing Tangent Software Co. Ltd.
// = FileName	:   TSafeHeapMem.h
// = Version	:   ver2.0
// = Author		:   xlc
// = CreateDate	:   2002-09-09
// = Description:   类的声明 可以自由浅拷贝的堆内存资源
// = Maintainers: 
//                  
//-----------------------------------------------------------------------------+
#ifndef _TSAFEHEAPMEM_H_
#define _TSAFEHEAPMEM_H_

#ifndef _TSAFERESOURCE_H_
#include "TSafeResource.h"
#endif

template<class T> class TSafeHeapMem : public TSafeResource
{
public:

	//初次分配堆内存
	TSafeHeapMem(long size = 0);

	//放弃堆空间
	virtual ~TSafeHeapMem();

	//分配一个新资源并放弃原资源
	void Realloc(long size);

	T& operator*();

	T& operator[](long index);

protected:
	
	//释放堆内存
	virtual void Release();

	//获取堆内存
	virtual void Apply(TSafeResource& source);

protected:

	T* p;
};

template<class T>
TSafeHeapMem<T>::TSafeHeapMem(long size)
{
	//初次分配堆内存
	//如果要求的长度<=0,则分配一个空内存，
	if(size <= 0)
	{
		p = NULL;
	}
	else
	{
		p = new T[size];
	}
}

template<class T>
void TSafeHeapMem<T>::Realloc(long size)
{
	//分配一个新资源并放弃原资源
	Detach();
	if(size <= 0)
	{
		p = NULL;
	}
	else
	{
		p = new T[size];
	}
}

template<class T>
TSafeHeapMem<T>::~TSafeHeapMem()
{
	//放弃堆空间
	Detach();
}

template<class T>
T& TSafeHeapMem<T>::operator*()
{
	//p 不能为null
	return *p;
}

template<class T>
T& TSafeHeapMem<T>::operator[](long index)
{
	//index必须是有效的
	return p[index];
}

template<class T>
void TSafeHeapMem<T>::Release()
{
	//释放堆内存
	//如果内存为不存在，则不进行任何操作。
	if(p != NULL)
	{
		delete[] p;
		p = NULL;
	}
}

template<class T>
void TSafeHeapMem<T>::Apply(TSafeResource&source)
{
	//获取堆内存
	//得到它的地址，
	p = ((TSafeHeapMem<T>&)source).p;
}

#endif