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CDynamicSimpleDataBufferTT::CDynamicSimpleDataBufferT(DWORD dwMaxSize)

m_dwMaxDataSize(dwMaxSize) {m_pData new T[dwMaxSize];if (m_pData NULL)throw std:: bad_alloc(new T Array Failed);m_dwDataLen 0;assert(m_pData ! NULL);assert(m_dwDataLen 0); }//清空数据函数 template class T void CDynamicSimpleDataBufferTT::ClearData() {if (m_pData)delete []m_pData;m_pData NULL;m_dwDataLen 0; }//赋值函数 template class T BOOL CDynamicSimpleDataBufferTT::SetData(ConstDataTypePointer pData, DWORD dwSize) {int i;if (dwSize m_dwMaxDataSize)return FALSE;for (i 0; i (int)dwSize; i)m_pData[i] pData[i];m_dwDataLen dwSize;return TRUE; } 析构函数自动调用了Clear函数释放了内存这样就不怕退出的时候出现内存泄漏。 4.数据引用类 在前面讲解的静态缓冲区和动态缓冲区内部都需要开辟空间而数据引用类不需要开辟空间CRefSimpleDataBufferT的具体实现如下 template class T class CRefSimpleDataBufferT : public CSimpleDataBufferAdapterT { public:CRefSimpleDataBufferT() { }CRefSimpleDataBufferT(ConstDataTypePointer pBuffer, DWORD dwSize);virtual ~CRefSimpleDataBufferT() { }public:BOOL SetData(ConstDataTypePointer pBuffer, DWORD dwSize);void Clear(); };template class T CRefSimpleDataBufferTT::CRefSimpleDataBufferT(ConstDataTypePointer pBuffer, DWORD dwSize) {m_pData const_castDataTypePointer(pBuffer);m_dwDataLen dwSize; }template class T void CRefSimpleDataBufferTT::Clear() {if (m_pData)delete []m_pData;m_pData NULL;m_dwDataLen 0; }template class T BOOL CRefSimpleDataBufferTT::SetData(typename CRefSimpleDataBufferTT::ConstDataTypePointer pBuffer, DWORD dwSize) {Clear();m_pData const_castDataTypePointer(pBuffer);m_dwDataLen dwSize;return TRUE; } 从实现的代码来看如果引用的数据是动态分配的就可以调用Clear函数释放内存反之则不需要调用。 5.自动数据引用类 自动数据引用类就是引用外部的动态分配的数据源并自动释放这个数据源的内存。CAutoRefSimpleDataBufferT的实现代码如下 //自动释放动态分配的数据引用类 template class T class CAutoRefSimpleDataBufferT : public CRefSimpleDataBufferTT { public:CAutoRefSimpleDataBufferT() { }CAutoRefSimpleDataBufferT(ConstDataTypePointer pBuffer, DWORD dwSize);CAutoRefSimpleDataBufferT(ConstDataTypePointer pBuffer);void Clear();DataTypePointer operator-() { return GetData(); }ConstDataTypePointer operator-() const { return GetData(); }virtual ~CAutoRefSimpleDataBufferT(); };template class T CAutoRefSimpleDataBufferTT::CAutoRefSimpleDataBufferT(typename CAutoRefSimpleDataBufferTT::ConstDataTypePointer pBuffer, DWORD dwSize)

CRefSimpleDataBufferTT(pBuffer, dwSize) { }template class T CAutoRefSimpleDataBufferTT::CAutoRefSimpleDataBufferT(typename CAutoRefSimpleDataBufferTT::ConstDataTypePointer pBuffer)

CRefSimpleDataBufferTT(pBuffer, 1) { }template class T void CAutoRefSimpleDataBufferTT::Clear() {if (1 m_dwDataLen)delete m_pData;elseCRefSimpleDataBufferTT::Clear(); }template class T CAutoRefSimpleDataBufferTT::~CAutoRefSimpleDataBufferT() {Clear(); } CAutoRefSimpleDataBufferT和CRefSimpleDataBufferT的不同点就在于析构函数自动调用了Clear函数释放了数据源的内存。 6.几种缓冲区的类关系图 7.注意事项 1静态成员变量的初始化静态成员变量需要在类外进行初始化并且只能初始化一次。 2线程安全如果多个线程可能同时访问这个静态缓冲区你需要实现适当的同步机制来避免数据竞争和不一致。 3资源管理静态缓冲区在程序结束时自动销毁但如果你在其中存储了动态分配的资源如指针指向的堆内存你需要确保在程序结束前正确释放这些资源。 4性能考虑静态缓冲区大小固定如果缓冲区大小设置不当可能会导致频繁的内存溢出或内存浪费。 5并发访问在并发环境中如果多个线程可能同时写入或读取缓冲区需要考虑使用互斥锁如std::mutex来同步访问。 8.完整代码 Noncopyable.h /************************************************************************// 功能: 防止拷贝类// 备注: ************************************************************************/ #pragma onceclass CNoncopyable { public:CNoncopyable() {}~CNoncopyable() {}protected:CNoncopyable(const CNoncopyable src); //拷贝构造函数const CNoncopyable operator(const CNoncopyable src); //赋值函数 }; SimpleDataBuffer.h #pragma once #include Noncopyable.h #include assert.h #include new #include stdexcept using namespace std;#define MAX_STATIC_SIMPLE_BUFFER_SIZE (4*1024) //4K #define MAX_DYNAMIC_SIMPLE_BUFFER_SIZE (8001024) //800Ktemplate class T class CSimpleDataBufferBase : public CNoncopyable { public:typedef T DataType;typedef T DataTypePointer;typedef T DataTypeReference;typedef const T ConstDataType;typedef const T* ConstDataTypePointer;typedef const T ConstDataTypeReference;public:CSimpleDataBufferBase() {}virtual ~CSimpleDataBufferBase() {}public:virtual DWORD GetSize() const 0;virtual DataTypePointer GetData() 0;virtual ConstDataTypePointer GetData() const 0;virtual DWORD GetMaxSize() const 0;operator DataTypePointer() { return GetData(); } DataTypeReference operator*() { return *GetData(); }DataTypeReference operator;virtual BOOL SetData(ConstDataTypePointer pData, DWORD dwSize) 0;virtual void SetSize(DWORD dwSize) 0;virtual void Clear() 0; };template class T typename CSimpleDataBufferBaseT::DataTypeReference CSimpleDataBufferBaseT::operator {if ( (nIndex 0) (nIndex (int)GetSize())){DataTypePointer pData GetData();return pData[nIndex];}else{throw std::out_of_range(invalid datanIndex position);} }//数据静态分配 template class T class CStaticSimpleDataBufferT : public CSimpleDataBufferBaseT { public:CStaticSimpleDataBufferT(DWORD dwMaxSize MAX_STATIC_SIMPLE_BUFFER_SIZE);virtual ~CStaticSimpleDataBufferT() { }public:DWORD GetSize() const { return m_dwDataLen; }DataTypePointer GetData() { return m_sData ;}ConstDataTypePointer GetData() const { return m_sData ;}BOOL SetData(ConstDataTypePointer pData, DWORD dwSize);void SetSize(DWORD dwSize) { m_dwDataLen dwSize; }DWORD GetMaxSize() const { return m_dwMaxDataSize; }void Clear() { m_dwDataLen 0; }private:DataType m_sData[MAX_STATIC_SIMPLE_BUFFER_SIZE];DWORD m_dwDataLen;const DWORD m_dwMaxDataSize; };template class T CStaticSimpleDataBufferTT::CStaticSimpleDataBufferT(DWORD dwMaxSize)

m_dwDataLen(0),m_dwMaxDataSize(dwMaxSize) { }template class T BOOL CStaticSimpleDataBufferTT::SetData(ConstDataTypePointer pData, DWORD dwSize) {int i;if (dwSize m_dwMaxDataSize)return FALSE;for (i 0; i (int)dwSize; i)m_sData[i] pData[i];m_dwDataLen dwSize;return TRUE; } /// template class T class CSimpleDataBufferAdapter : public CSimpleDataBufferBaseT { public:CSimpleDataBufferAdapter() : m_pData(NULL),m_dwDataLen(0) { }virtual ~CSimpleDataBufferAdapter() { }public:DWORD GetSize() const { return m_dwDataLen; }BOOL SetData(ConstDataTypePointer pData, DWORD dwSize) { assert(0); return FALSE; }void SetSize(DWORD dwSize) { m_dwDataLen dwSize; }DWORD GetMaxSize() const { assert(0); return 0; }void Clear() { assert(0); }DataTypePointer GetData() { return m_pData ;}ConstDataTypePointer GetData() const { return m_pData ;}protected:DataTypePointer m_pData;DWORD m_dwDataLen; };/ template class T class CDynamicSimpleDataBufferT : public CSimpleDataBufferAdapterT { public:CDynamicSimpleDataBufferT(DWORD dwMaxSize MAX_DYNAMIC_SIMPLE_BUFFER_SIZE);virtual ~CDynamicSimpleDataBufferT() { ClearData(); }public:void Clear() { m_dwDataLen 0; }DWORD GetMaxSize() const { return m_dwMaxDataSize; }BOOL SetData(ConstDataTypePointer pData, DWORD dwSize);protected:void ClearData();private:const DWORD m_dwMaxDataSize; };template class T CDynamicSimpleDataBufferTT::CDynamicSimpleDataBufferT(DWORD dwMaxSize)

m_dwMaxDataSize(dwMaxSize) {m_pData new T[dwMaxSize];if (m_pData NULL)throw std:: bad_alloc(new T Array Failed);m_dwDataLen 0;assert(m_pData ! NULL);assert(m_dwDataLen 0); }template class T void CDynamicSimpleDataBufferTT::ClearData() {if (m_pData)delete []m_pData;m_pData NULL;m_dwDataLen 0; }template class T BOOL CDynamicSimpleDataBufferTT::SetData(ConstDataTypePointer pData, DWORD dwSize) {int i;if (dwSize m_dwMaxDataSize)return FALSE;for (i 0; i (int)dwSize; i)m_pData[i] pData[i];m_dwDataLen dwSize;return TRUE; } // template class T class CRefSimpleDataBufferT : public CSimpleDataBufferAdapterT { public:CRefSimpleDataBufferT() { }CRefSimpleDataBufferT(ConstDataTypePointer pBuffer, DWORD dwSize);virtual ~CRefSimpleDataBufferT() { }public:BOOL SetData(ConstDataTypePointer pBuffer, DWORD dwSize);void Clear(); };template class T CRefSimpleDataBufferTT::CRefSimpleDataBufferT(ConstDataTypePointer pBuffer, DWORD dwSize) {m_pData const_castDataTypePointer(pBuffer);m_dwDataLen dwSize; }template class T void CRefSimpleDataBufferTT::Clear() {if (m_pData)delete []m_pData;m_pData NULL;m_dwDataLen 0; }template class T BOOL CRefSimpleDataBufferTT::SetData(typename CRefSimpleDataBufferTT::ConstDataTypePointer pBuffer, DWORD dwSize) {Clear();m_pData const_castDataTypePointer(pBuffer);m_dwDataLen dwSize;return TRUE; }//自动释放动态分配的数据引用类 template class T class CAutoRefSimpleDataBufferT : public CRefSimpleDataBufferTT { public:CAutoRefSimpleDataBufferT() { }CAutoRefSimpleDataBufferT(ConstDataTypePointer pBuffer, DWORD dwSize);CAutoRefSimpleDataBufferT(ConstDataTypePointer pBuffer);void Clear();DataTypePointer operator-() { return GetData(); }ConstDataTypePointer operator-() const { return GetData(); }virtual ~CAutoRefSimpleDataBufferT(); };template class T CAutoRefSimpleDataBufferTT::CAutoRefSimpleDataBufferT(typename CAutoRefSimpleDataBufferTT::ConstDataTypePointer pBuffer, DWORD dwSize)

CRefSimpleDataBufferTT(pBuffer, dwSize) { }template class T CAutoRefSimpleDataBufferTT::CAutoRefSimpleDataBufferT(typename CAutoRefSimpleDataBufferTT::ConstDataTypePointer pBuffer)

CRefSimpleDataBufferTT(pBuffer, 1) { }template class T void CAutoRefSimpleDataBufferTT::Clear() {if (1 m_dwDataLen)delete m_pData;elseCRefSimpleDataBufferTT::Clear(); }template class T CAutoRefSimpleDataBufferTT::~CAutoRefSimpleDataBufferT() {Clear(); }