用C++简单实现的——BlockingQueue类(java)

最近，简单整理完Linux线程方面的知识点，突发奇想的想写个线程池来玩玩。经过多方的考虑，决定仿java的线程池来写。由于没有学过java，最后的结果可能差距很大，好像扯远了回到正题来。Java线程池中使用到了BlockingQueue类那就先来试着用C++来实现它吧！

最终只实现了BlockingQueue中的ArrayBlockingQueue(基于数组的阻塞队列实现)和LinkedBlockingQueue(基于链表的阻塞队列)也只实现了BlockingQueue中4个核心的方法。好像对线程池来说够用了。

1.Mutext.h

#ifndef __MUTEX_H__  #define __MUTEX_H__    #include <pthread.h>    class CMutexLock  {  public:  explicit CMutexLock()  {  pthread_mutex_init(&m_Mutex, NULL);  }    ~CMutexLock()  {  pthread_mutex_destroy(&m_Mutex);  }    void lock()  {  pthread_mutex_lock(&m_Mutex);  }    void unlock()  {  pthread_mutex_unlock(&m_Mutex);  }    pthread_mutex_t *get()  {  return &m_Mutex;  }    private:  friend class CCondition;          pthread_mutex_t m_Mutex;  };        class CMutexLockPart      {      public:          explicit CMutexLockPart(CMutexLock &MutexLock)                  :m_MutexLock(MutexLock)          {              m_MutexLock.lock();          }            ~CMutexLockPart()          {              m_MutexLock.unlock();          }                private:          CMutexLock &m_MutexLock;      };    #endif  //#ifndef __MUTEX_H__ 

2.Condition.h

#ifndef __CONDITION_H__  #define __CONDITION_H__    #include "Mutex.h" class CCondition  {  public:  explicit CCondition(CMutexLock &MutexLock):m_MutexLock(MutexLock)  {  pthread_cond_init(&m_Condition, NULL);}  ~CCondition()  {  pthread_cond_destroy(&m_Condition);  }  void wait()  {  pthread_cond_wait(&m_Condition, m_MutexLock.get());  }  void signal()  {  pthread_cond_signal(&m_Condition);}  void broadcast()  {  pthread_cond_broadcast(&m_Condition);  }  private:  CMutexLock &m_MutexLock;  pthread_cond_t m_Condition;  };#endif//#ifndef __CONDITION_H__  

3.BlockingQueue.h

#ifndef __BLOCKING_QUEUE_H__#define __BLOCKING_QUEUE_H__//在使用队列的时候需要注意，是否需要定义拷贝构造和赋值函数template<typename T>class CBlockingQueue{public:CBlockingQueue() { }virtual ~CBlockingQueue() { }//放入数据的方法virtual bool offer(const T &anObject) = 0;//不阻塞当前执行方法的线程 virtual void put(const T &anObject) = 0;//会阻塞当前执行方法的线程//获取数据的方法(注：如果队列为空调用poll则返回一个初始化的T，当做未定义)virtual T poll(void) = 0;//取走BlockingQueue首位的对象,调用改方法必须确保队列不为空virtual T take(void) = 0;//取走BlockingQueue首位的对象，若队列为空则阻塞//添加一个方法，用来判断队列是否为空virtual bool empty(void) = 0;//添加一个方法，用来查询队列中还有多少数据virtual int size(void) = 0;//添加一个方法，用来判断队列是否是满的virtual bool full(void) = 0;};#endif//#ifndef __BLOCKING_QUEUE_H__

4.ArrayBlockingQueue.h

#ifndef __ARRAY_BLOCKING_QUEUE_H__#define __ARRAY_BLOCKING_QUEUE_H__#include "BlockingQueue.h"#include "Mutex.h"#include "Condition.h"//目前觉得这个类存在问题：在取出元素的时候，是否需要显示的调用析构函数。//这需要看T的定义以及深拷贝构造和赋值函数了。template<typename T>class CArrayBlockingQueue:public CBlockingQueue<T>{public:CArrayBlockingQueue(int iSize):m_iSize(iSize),m_iCount(0),m_MutexLock(),m_Condition(m_MutexLock){m_pArray = new T[iSize];m_pStart = m_pArray;m_pEnd = m_pArray;}~CArrayBlockingQueue(){delete[] m_pArray;}virtual bool offer(const T &anObject){//如果有可能将anObject添加到队列中，如果可以容纳，则返回          //成功，否则返回失败。本方法不阻塞当前执行方法的线程 CMutexLockPart PartLock(m_MutexLock);if (m_iCount < m_iSize){//队列还未满的情况 *m_pEnd = anObject;m_iCount++;m_pEnd++;if (m_pEnd == m_pArray + m_iSize){m_pEnd = m_pArray;}m_Condition.signal();return true;}return false;}virtual void put(const T &anObject){//添加元素到队列里，如果容量满了会阻塞到容量不满m_MutexLock.lock();if(m_iCount == m_iSize){m_Condition.wait();//队列满就阻塞}//队列还未满的情况*m_pEnd = anObject;m_pEnd++;if (m_pEnd == m_pArray + m_iSize){m_pEnd = m_pArray;}m_iCount++;m_MutexLock.unlock();m_Condition.signal();}virtual T poll(void){//删除队列头部元素，如果队列为空，则是未定义的行为，否则返回元素. CMutexLockPart PartLock(m_MutexLock);if (m_iCount <= 0){//队列为空  T tNull;return tNull;}T tRet = *m_pStart;m_pStart++;if (m_pStart == m_pArray + m_iSize){m_pStart = m_pArray;}m_iCount--;return tRet;}virtual T take(void){//删除队列头部元素，如果队列为空，则阻塞。m_MutexLock.lock();if (m_iCount <= 0){m_Condition.wait(); //队列空就阻塞 }T tRet = *m_pStart;m_pStart++;if (m_pStart == m_pArray + m_iSize){m_pStart = m_pArray;}m_iCount--;m_MutexLock.unlock();return tRet;}virtual bool empty(void){//如果m_iCount == 0那么队列就为空if (m_iCount == 0)return true;return false;}virtual int size(void){return m_iCount;}virtual bool full(void){return m_iSize == m_iCount;}private:T *m_pArray;int m_iSize;int m_iCount;T *m_pStart;T *m_pEnd;CMutexLock m_MutexLock;CCondition m_Condition;};#endif//#ifndef __ARRAY_BLOCKING_QUEUE_H__

5.LinkedBlockingQueue.h

#ifndef __LINKED_BLOCKING_QUEUE_H__#define __LINKED_BLOCKING_QUEUE_H__#include <list>#include <limits.h>#include "Mutex.h"#include "Condition.h"#include "BlockingQueue.h"template<typename T>class CLinkedBlockingQueue:public CBlockingQueue<T>{public:CLinkedBlockingQueue(int iSize = INT_MAX):m_listQueue(),m_iSize(iSize),m_MutexLock(),m_Condition(m_MutexLock){}~CLinkedBlockingQueue(){m_listQueue.clear();}bool offer(const T &anObject){//如果有可能将anObject添加到队列中，如果可以容纳，则返回          //成功，否则返回失败。本方法不阻塞当前执行方法的线程 CMutexLockPart PartLock(m_MutexLock);if (static_cast<int>(m_listQueue.size()) >= m_iSize){//超过了队列的最大值 ֵreturn false;}m_listQueue.push_back(anObject);return true;}void put(const T &anObject){//添加元素到队列里，如果容量满了会阻塞到容量不满m_MutexLock.lock();if (static_cast<int>(m_listQueue.size()) >= m_iSize){ //超过了队列的最大值,阻塞等待 m_Condition.wait();}m_listQueue.push_back(anObject);m_MutexLock.unlock();m_Condition.signal();}T poll(void){//删除队列头部元素，如果队列为空，则该行为未定义。否则返回元素.CMutexLockPart PartLock(m_MutexLock);if (m_listQueue.empty()){//队列为空 T tNULL;return tNULL;}T tRet = m_listQueue.front();m_listQueue.pop_front();return tRet;}T take(void){//删除队列头部元素，如果队列为空，则阻塞。m_MutexLock.lock();if (m_listQueue.empty()){m_Condition.wait(); //队列空就阻塞 }T tRet = m_listQueue.front();m_listQueue.pop_front();m_MutexLock.unlock();return tRet;}bool empty(void){//直接调用STL提供的方法就行了return m_listQueue.empty();}int size(void){return m_listQueue.size();}bool full(void){return m_iSize == static_cast<int>(m_listQueue.size());}private://这里直接使用STL的链表，后面会有数据结构专题      //这边就直接使用现成的，嘿嘿 std::list<T> m_listQueue;int m_iSize;CMutexLock m_MutexLock;CCondition m_Condition;};#endif//#ifndef __LINKED_BLOCKING_QUEUE_H__

6.main.cpp

#include <stdio.h>#include <unistd.h>#include <pthread.h>#include "ArrayBlockingQueue.h"#include "LinkedBlockingQueue.h"using namespace std;void *pthreadFunc1(void *pArg){printf("pthreadFunc1 start runing ...\n");CBlockingQueue<int> *pBlockingQueue = static_cast<CBlockingQueue<int> *>(pArg);bool bRet;for (int i = 0; i < 25; i++){bRet = pBlockingQueue->offer(i);if (bRet == false)printf("offer(%d) false, queue fill\n", i);elseprintf("offer(%d) true\n", i);usleep(1000);}printf("pthreadFunc1 end runing ...\n");pthread_exit((void *)1);}void *pthreadFunc2(void *pArg){printf("pthreadFunc2 start runing ...\n");CBlockingQueue<int> *pBlockingQueue = static_cast<CBlockingQueue<int> *>(pArg);int iValue;bool bRet;for (int i = 0; i < 50; i++){iValue = pBlockingQueue->poll(bRet);if (bRet == false)printf("poll() false, queue empty\n");elseprintf("poll() value = %d\n", iValue);usleep(500);}printf("pthreadFunc2 end runing ...\n");pthread_exit((void *)2);}void *pthreadFunc3(void *pArg){printf("pthreadFunc3 start runing ...\n");CBlockingQueue<int> *pBlockingQueue = static_cast<CBlockingQueue<int> *>(pArg);for (int i = 0; i < 50; i++){pBlockingQueue->put(i);printf("put(%d) true\n", i);usleep(100);}printf("pthreadFunc3 end runing ...\n");pthread_exit((void *)1);}void *pthreadFunc4(void *pArg){printf("pthreadFunc4 start runing ...\n");CBlockingQueue<int> *pBlockingQueue = static_cast<CBlockingQueue<int> *>(pArg);int iValue;for (int i = 0; i < 50; i++){iValue = pBlockingQueue->take();printf("take() value = %d\n", iValue);usleep(70);}printf("pthreadFunc4 end runing ...\n");pthread_exit((void *)2);}void testOfferAndPoll(void){//CBlockingQueue<int> *pBlockingQueue = new CArrayBlockingQueue<int>(10);CBlockingQueue<int> *pBlockingQueue = new CLinkedBlockingQueue<int>();pthread_t pthreadId1;pthread_t pthreadId2;pthread_create(&pthreadId1, NULL, &pthreadFunc1, pBlockingQueue);pthread_create(&pthreadId2, NULL, &pthreadFunc2, pBlockingQueue);pthread_join(pthreadId1, NULL);pthread_join(pthreadId2, NULL);delete pBlockingQueue;}void testPutAndTake(void){//CBlockingQueue<int> *pBlockingQueue = new CArrayBlockingQueue<int>(10);CBlockingQueue<int> *pBlockingQueue = new CLinkedBlockingQueue<int>();pthread_t pthreadId1;pthread_t pthreadId2;pthread_create(&pthreadId1, NULL, &pthreadFunc3, pBlockingQueue);pthread_create(&pthreadId2, NULL, &pthreadFunc4, pBlockingQueue);pthread_join(pthreadId1, NULL);pthread_join(pthreadId2, NULL);delete pBlockingQueue;}int main(void){testOfferAndPoll();testPutAndTake();return 0;}

测试的结果好像还行。