我的组件之线程类

上一篇，我说到了 OwnerPolicy 很重要，究竟它有什么样的表现呢？请看下面，Thread 类的实现。

//--------------------------------------------------------------////Copyright (C) 2009 - All Rights Reserved.////Author:LiuYin//File:Thread//Version: 1.0//Date: 2009-8-10////Purpose:////--------------------------------------------------------------#ifndef Thread_H#define Thread_H//////////////////////////////////////////////////////////////////////////#include <WTypes.h>#include <Process.h>//////////////////////////////////////////////////////////////////////////#include "OwnerPolicy.h"//////////////////////////////////////////////////////////////////////////template <class Owner>class ThreadT:public OwnerPolicy<Owner>{typedef ThreadT<Owner> This;//////////////////////////////////////////////////////////////////////////struct ThreadParam{This *pThis;LONG lCount;};//////////////////////////////////////////////////////////////////////////public:ThreadT():m_hEventExit(NULL), m_lThreadCount(0){m_hEventExit = CreateEvent(NULL, TRUE, FALSE, NULL);}~ThreadT(){Stop();if (m_hEventExit != NULL) {CloseHandle(m_hEventExit);m_hEventExit = NULL;}}DWORD Start(DWORD dwCount){const DWORD MAX_COUNT_ONE_TIME = 128;if (m_hEventExit == NULL) {return 0;}dwCount = ((dwCount > 0) && (dwCount < MAX_COUNT_ONE_TIME)) ? dwCount : MAX_COUNT_ONE_TIME;ThreadParam threadParam;threadParam.pThis= this;threadParam.lCount= dwCount;DWORD dwCreate = 0;HANDLE hThread[MAX_COUNT_ONE_TIME] = { 0 };for (DWORD i=0; i<dwCount; ++i) {hThread[i] = (HANDLE) _beginthreadex(NULL, 0, ThreadT::_SvcBase, &threadParam, 0, NULL);if (hThread[i] != NULL) {++dwCreate;}else {InterlockedDecrement(&(threadParam.lCount));}}while (InterlockedCompareExchange(&(threadParam.lCount), 0, 0) > 0) {Sleep(0);}for (DWORD i=0; i<dwCount; ++i) {if (hThread[i] == NULL) {continue;}CloseHandle(hThread[i]);hThread[i] = NULL;}return dwCreate;}VOID Stop(){SetEvent(m_hEventExit);while (InterlockedCompareExchange(&m_lThreadCount, 0, 0) > 0) {Sleep(0);}ResetEvent(m_hEventExit);}private:static unsigned __stdcall _SvcBase(LPVOID pParam){ThreadParam *pThreadParam = static_cast<ThreadParam *>(pParam);pThreadParam->pThis->Svc(pThreadParam);return 0xDead;}VOID Svc(ThreadParam *pThreadParam){InterlockedIncrement(&m_lThreadCount);InterlockedDecrement(&(pThreadParam->lCount));Owner *pOwner = this->owner();if (pOwner == NULL) {goto Exit;}pOwner->Svc(this, m_hEventExit);Exit:InterlockedDecrement(&m_lThreadCount);}private:HANDLE m_hEventExit;LONG m_lThreadCount;};//////////////////////////////////////////////////////////////////////////#endif

示例用法如下：

#include <stdio.h>#include "Thread.h"//////////////////////////////////////////////////////////////////////////class YourClass{typedef ThreadT<YourClass> CThread;public:YourClass(){m_threadA.owner(this);m_threadB.owner(this);}VOID Start(){m_threadA.Start(1);m_threadB.Start(2);}VOID Svc(CThread *pThread, HANDLE hEventExit){if (pThread == &m_threadA) {while (TRUE) {if (WaitForSingleObject(hEventExit, 100) != WAIT_TIMEOUT) {break;}printf("This is thread A!\n");}}if (pThread == &m_threadB) {while (TRUE) {if (WaitForSingleObject(hEventExit, 100) != WAIT_TIMEOUT) {break;}OutputDebugString("This is thread B!\n");}}}VOID Stop(){m_threadA.Stop();m_threadB.Stop();}private:CThread m_threadA;CThread m_threadB;};//////////////////////////////////////////////////////////////////////////int main(){YourClass yourClass;yourClass.Start();Sleep(1000 * 4);yourClass.Stop();return 0;}

看到了吗？这样我的 Thread 类，重用性就非常高了，因为它和其他具体的类，其实没有一点关系。如果我要在其他的类里使用多线程也只用增加接口 Svc 及少量代码就可以了。利用模板，我们消除了它和其他类的联系，唯一的联系只在于 YourClass 中的 Svc 和 Thread 的 Start 及 Stop 接口。