12.队列的应用-事件驱动编程

#include <stdio.h>
#include <process.h>
#include <stdlib.h>
#include <time.h>
#include <Windows.h>

#include "JWArray.h"

JWArray(event)		*pEventQueue;					//事件队列
JWArrayElem(event)	eventElem;						//事件元素
JWArray(window)		*pWindowsQueue[5];				//窗口队列，为了使用方便，下标从1开始
JWArrayElem(window)	windowElem;						//窗口元素
int					nCloseTime = 100;				//银行关闭时间

JWArray_BOOL EventCompare(JWArrayElem(event) elem1, JWArrayElem(event) elem2);
void ShowState(int nCurTime);
void Init();
void Clear();
int  CalcMinWindow();
void CustomerArrived(int nArriveTime);
void CustomerLeave(int nCurTime, int iLeave);
void EventPump();
void ShowState(int nCurTime);


int main(int argc, char *argv[])
{
	//开启事件泵
	EventPump();

	return 0;
}

/**
 *功能:	事件队列元素比较函数
 *参数:	elem1,elem2 -- 两个事件队列元素
 *返回:	elem1的发生时间小于elem2则返回JWArray_TRUE，否则返回JWArray_FALSE
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
JWArray_BOOL EventCompare(JWArrayElem(event) elem1, JWArrayElem(event) elem2)
{
	return elem1.nOccurTime  < elem2.nOccurTime ? JWARRAY_TRUE : JWARRAY_FALSE;
}

/**
 *功能:	初始化--分配事件队列和窗口队列，在事件队列插入启动的客户到达事件
 *参数:	无
 *返回:	无
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
void Init()
{
	int i;

	//分配队列
	pEventQueue = JWArrayCreate(event)(20, 10);
	for (i = 1; i < 5; i++)
	{
		pWindowsQueue[i] = JWArrayCreate(window)(20, 10);
	}

	//在事件队列插入第一个客户到达事件
	eventElem.nOccurTime	= 0;
	eventElem.nType			= 0;

	JWArrayEnQueue(event)(pEventQueue, eventElem);
}

/**
 *功能:	清理工作--清理事件队列和窗口队列
 *参数:	无
 *返回:	无
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
void Clear()
{
	int i;

	//清理队列
	JWArrayDestroy(event)(pEventQueue);
	for (i = 1; i < 5; i++)
	{
		JWArrayDestroy(window)(pWindowsQueue[i]);
	}
}

/**
 *功能:	计算当前窗口队列前人数最少的窗口号
 *参数:	无
 *返回:	人数最少的窗口队列号
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
int CalcMinWindow()
{
	int nLength ;
	int i ;
	int nIndex ;
	
	nIndex	 = 1;
	nLength  = JWArrayGetLength(window)(pWindowsQueue[1]);
	for (i = 2; i <=4 ; i++)
	{
		if (JWArrayGetLength(window)(pWindowsQueue[i]) < nLength)
		{
			nIndex = i;
			nLength  = JWArrayGetLength(window)(pWindowsQueue[i]);
		}
	}

	return nIndex;
}

/**
 *功能:	处理客户到达事件
 *参数:	nArriveTime--客户到达的时间
 *返回:	无
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
void CustomerArrived(int nArriveTime)
{
	int i;
	int nDurationtime;			//当前客户办理业务消耗时间
	int nNextInterTime;			//距离下一个客户到达时间

	//随机生成nDurationtime和nNextInterTime
	srand( (unsigned)time( NULL ) );
	nDurationtime = rand() % 30 +1;
	nNextInterTime = rand() % 5 +1;

	//设置下一个客户到达事件
	if (nArriveTime + nNextInterTime < nCloseTime)
	{
		eventElem.nOccurTime = nArriveTime + nNextInterTime;
		eventElem.nType = 0;

		JWArrayOrderInsert(event)(pEventQueue, eventElem, EventCompare);
	}

	//设置当前窗口排列队形
	i = CalcMinWindow();
	windowElem.nArriveTime = nArriveTime;
	windowElem.nDurationTime = nDurationtime;
	JWArrayEnQueue(window)(pWindowsQueue[i], windowElem);

	//如果是第一个到达客户，插入一个离开事件，否则此后的离开事件在前一个离开事件发生后插入
	if (JWArrayGetLength(window)(pWindowsQueue[i]) == 1)
	{
		eventElem.nOccurTime = nArriveTime + nDurationtime;
		eventElem.nType = i;

		JWArrayOrderInsert(event)(pEventQueue, eventElem, EventCompare);
	}
}

/**
 *功能:	处理客户离开事件
 *参数:	nCurTime--客户离开事件发生时间，iLeave--客户离开事件发生的窗口队列号
 *返回:	无
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
void CustomerLeave(int nCurTime, int iLeave)
{
	//window队列出列
	JWArrayDeQueue(window)(pWindowsQueue[iLeave], NULL);

	//设置下一个客户离开时间
	if (JWARRAY_FALSE == JWArrayIsEmpty(window)(pWindowsQueue[iLeave]))
	{
		JWArrayGetHead(window)(pWindowsQueue[iLeave], &windowElem);

		eventElem.nOccurTime = nCurTime + windowElem.nDurationTime;//注意这里实际离开时间是当前离开事件发生的时间加上下一个客户要办理业务的时间，不能写成下一个客户到达的时间加上下一个客户要办理业务的时间，这是不对的，因为客户到达时不能立即开始办理，要等待!!!
		eventElem.nType = iLeave;

		JWArrayOrderInsert(event)(pEventQueue, eventElem, EventCompare);
	}
}

/**
 *功能:	开启消息泵，依据时间对事件队列处理从而推动整个事件的发生
 *参数:	无
 *返回:	无
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
void EventPump()
{
	int i=0;

	Init();

	do 
	{
		if (JWARRAY_FALSE != JWArrayGetHead(event)(pEventQueue, &eventElem))
		{
			while (eventElem.nOccurTime == i)//处理当前时刻可能同时存在的多个事件
			{
				JWArrayDeQueue(event)(pEventQueue, &eventElem);

				if (eventElem.nType == 0)
				{
					CustomerArrived(eventElem.nOccurTime);
				}
				else
				{
					CustomerLeave(i, eventElem.nType);
				}

				if (JWARRAY_FALSE == JWArrayGetHead(event)(pEventQueue, &eventElem))
				{
					break;
				}
			}
		}
		else
		{
			break;
		}

		ShowState(i++);
		Sleep(100);
	} while (1);

	Clear();
}

/**
 *功能:	显示当前事件队列和各个窗口队列的情况
 *参数:	无
 *返回:	无
 *其他:	2014/05/05 By Jim Wen Ver1.0
**/
void ShowState(int nCurTime)
{
	system("cls");
	printf("当前时间:%d\n\n", nCurTime);

	printf("--------------------------------------------------------------------------------\n");
	printf("事件队列\t");
	JWArrayTraverse(event)(pEventQueue, JWArrayPrintfElem(event));
	printf("\n--------------------------------------------------------------------------------\n\n");

	printf("\n--------------------------------------------------------------------------------\n");
	printf("窗口1\t");
	JWArrayTraverse(window)(pWindowsQueue[1], JWArrayPrintfElem(window));
	printf("\n--------------------------------------------------------------------------------\n");
	printf("窗口2\t");
	JWArrayTraverse(window)(pWindowsQueue[2], JWArrayPrintfElem(window));
	printf("\n--------------------------------------------------------------------------------\n");
	printf("窗口3\t");
	JWArrayTraverse(window)(pWindowsQueue[3], JWArrayPrintfElem(window));
	printf("\n--------------------------------------------------------------------------------\n");
	printf("窗口4\t");
	JWArrayTraverse(window)(pWindowsQueue[4], JWArrayPrintfElem(window));
	printf("\n--------------------------------------------------------------------------------\n");
}