一个Windows C++的线程池的实现

       此线程池所依赖的线程类，请参看《一个Windows C++的线程类实现》：该线程池程序没有完全按照C++类的设计思想来做，在CWorker和CThreadPoolExecutor类的封装上还需要做些改动。

头文件：

// CThreadPool.h: interface for the CThreadPool class.////////////////////////////////////////////////////////////////////////#ifndef __C_PLUS_CTHREADPOOL_HEADE#define __C_PLUS_CTHREADPOOL_HEADE#include <set>#include <list>#include <windows.h>#include "CThread.h"using namespace std;class CThreadPoolExecutor {public:CThreadPoolExecutor(); ~CThreadPoolExecutor(); // 初始化线程池，创建minThreads个线程 BOOL Init(unsigned int minThreads, unsigned int maxThreads, unsigned int maxPendingTasks); // 执行任务，若当前任务列表没满，则将此任务加入列表，返回TRUE // 若当前任务列表满,但小于最大线程数，将创建线程执行此任务，返回TRUE // 若当前任务列表满，且等于最大线程数，则丢弃此任务，返回FALSE BOOL Execute(Runnable* pRunnable); // 终止线程池，先制止塞入任务， // 然后等待直到任务列表为空， // 然后设置最小线程数量为0， // 清空垃圾丢中的任务 void Terminate(); // 返回线程池中当前的线程数量 unsigned int GetThreadPoolSize(); //friend class CWorker;Runnable * GetTask();static unsigned int WINAPI StaticThreadFunc(void* arg);public:class CWorker:public CThread{public:CWorker(CThreadPoolExecutor* pThreadPool, Runnable* pFirstTask=NULL);~CWorker();void Run();private:CThreadPoolExecutor* m_pThreadPool;Runnable* m_pFirstTask;volatile BOOL m_bRun;};typedef std::set<CWorker*> ThreadPool;typedef std::list<Runnable*> Tasks;typedef Tasks::iterator TasksItr;typedef ThreadPool::iterator ThreadPoolItr;ThreadPool m_ThreadPool;  ThreadPool m_TrashThread;Tasks m_Tasks;CRITICAL_SECTION m_csTasksLock;CRITICAL_SECTION m_csThreadPoolLock;volatile BOOL m_bRun;volatile BOOL m_bEnableInsertTask;volatile unsigned int m_minThreads;volatile unsigned int m_maxThreads;volatile unsigned int m_maxPendingTasks;};#endif 

CPP文件：

// CThreadPool.cpp: implementation of the CThreadPool class.////////////////////////////////////////////////////////////////////////#include "CThreadPoolExecutor.h"CThreadPoolExecutor::CWorker::CWorker(CThreadPoolExecutor* pThreadPool, Runnable* pFirstTask):  m_pThreadPool(pThreadPool),  m_pFirstTask(pFirstTask),   m_bRun(TRUE){  }CThreadPoolExecutor::CWorker::~CWorker(){  }// 直线任务的工作线程// 当前没有任务时，如果当前线程数量大于最小线程时，减少线程// 否则，执行清理程序，将线程类给释放掉void CThreadPoolExecutor::CWorker::Run(){Runnable* pTask = NULL;while ( m_bRun){if ( NULL == m_pFirstTask){pTask = m_pThreadPool->GetTask();}else{pTask = m_pFirstTask;m_pFirstTask = NULL;}if ( NULL == pTask){EnterCriticalSection(&(m_pThreadPool->m_csThreadPoolLock));if ( m_pThreadPool->GetThreadPoolSize()> m_pThreadPool->m_minThreads){ThreadPoolItr itr = m_pThreadPool->m_ThreadPool.find(this);if ( itr!=m_pThreadPool->m_ThreadPool.end()){m_pThreadPool->m_ThreadPool.erase(itr);m_pThreadPool->m_TrashThread.insert(this);}m_bRun = FALSE;}else{ThreadPoolItr itr = m_pThreadPool->m_TrashThread.begin();while ( itr!=m_pThreadPool->m_TrashThread.end()){(*itr)->Join();delete (*itr);m_pThreadPool->m_TrashThread.erase(itr);itr = m_pThreadPool->m_TrashThread.begin();}}// end elseLeaveCriticalSection(&(m_pThreadPool->m_csThreadPoolLock));continue;}// end ifelse{pTask->Run();pTask = NULL;}}// end while m_bRun} CThreadPoolExecutor::CThreadPoolExecutor():m_bRun(FALSE), m_bEnableInsertTask(FALSE){InitializeCriticalSection(&m_csTasksLock);InitializeCriticalSection(&m_csThreadPoolLock);}CThreadPoolExecutor::~CThreadPoolExecutor(){Terminate();DeleteCriticalSection(&m_csTasksLock);DeleteCriticalSection(&m_csThreadPoolLock);}BOOL CThreadPoolExecutor::Init(unsigned int minThreads, unsigned int maxThreads, unsigned int maxPendingTasks){if ( minThreads ==0){return FALSE;}if ( maxThreads < minThreads){return FALSE;}m_minThreads = minThreads;m_maxThreads = maxThreads;m_maxPendingTasks = maxPendingTasks;unsigned int i = m_ThreadPool.size();for ( ;i<minThreads; i++){CWorker* pWorker = new CWorker(this);if ( NULL == pWorker){return FALSE;}EnterCriticalSection(&m_csThreadPoolLock);m_ThreadPool.insert(pWorker);LeaveCriticalSection(&m_csThreadPoolLock);pWorker->Start();}m_bRun = TRUE;m_bEnableInsertTask = TRUE;return TRUE;}BOOL CThreadPoolExecutor::Execute(Runnable* pRunnable){if ( !m_bEnableInsertTask){return FALSE;}if ( NULL == pRunnable){return FALSE;}if ( m_Tasks.size()>=m_maxPendingTasks){if (m_ThreadPool.size()<m_maxThreads){CWorker* pWorker = new CWorker(this, pRunnable);if ( NULL == pWorker){return FALSE;}EnterCriticalSection(&m_csThreadPoolLock);m_ThreadPool.insert(pWorker);LeaveCriticalSection(&m_csThreadPoolLock);pWorker->Start();}else{return FALSE;}}else{EnterCriticalSection(&m_csTasksLock);m_Tasks.push_back(pRunnable);LeaveCriticalSection(&m_csTasksLock);}return TRUE;}Runnable* CThreadPoolExecutor::GetTask(){Runnable* Task = NULL;EnterCriticalSection(&m_csTasksLock);if ( !m_Tasks.empty()){Task = m_Tasks.front();m_Tasks.pop_front();}LeaveCriticalSection(&m_csTasksLock);return Task;}unsigned int CThreadPoolExecutor::GetThreadPoolSize(){return m_ThreadPool.size();}void CThreadPoolExecutor::Terminate(){m_bEnableInsertTask = FALSE;while (m_Tasks.size()>0){Sleep(1);}m_bRun = FALSE;m_minThreads = 0;m_maxThreads = 0;m_maxPendingTasks = 0;while ( m_ThreadPool.size()>0){Sleep(1);}EnterCriticalSection(&m_csThreadPoolLock);ThreadPoolItr itr = m_TrashThread.begin();while (itr!=m_TrashThread.end()){(*itr)->Join();delete(*itr);m_TrashThread.erase(itr);itr = m_TrashThread.begin();}LeaveCriticalSection(&m_csThreadPoolLock);}

测试程序：

#include <stdio.h>#include "CThread.h"#include "CThreadPoolExecutor.h"class Example:public Runnable{public:~Example(){printf("Example Destruction\n");}void Run(){printf("Hello CThread\n");}};int main(int argc, char* argvp[]){CThreadPoolExecutor* pExecutor = new CThreadPoolExecutor();pExecutor->Init(2,10,50);Example exam;for ( int i=0; i<100; i++){while ( !pExecutor->Execute(&exam)){}}pExecutor->Terminate();delete pExecutor;getchar();return 0;}