自定义线程池-c#的简单实现
下面是代码,希望大家提出更好的建议:
1.ThreadManager.cs
using System;
using System.Threading;
using System.Collections;
namespace CustomThreadPool
{
///<summary>
///线程管理器,会开启或唤醒一个线程去执行指定的回调方法
///</summary>
public class ThreadManager
{
//线程列表,静态
private static ArrayList threadList = new ArrayList();
//不允许创建实例
private ThreadManager()
{
}
///<summary>
///静态方法,开启或唤醒一个线程去执行指定的回调方法
///</summary>
///<param name="waitCallback">委托实例</param>
///<param name="obj">传递给回调方法的参数</param>
///<param name="timeOut">当没有可用的线程时的等待时间,
///以毫秒为单位</param>
///<returns></returns>
public static bool QueueUserWorkItem(WaitCallback waitCallback,
Object obj, int timeOut)
{
//锁住共享资源,实现线程安全
lock(threadList)
{
try
{
//如果线程列表为空,填充线程列表
if (threadList.Count == 0)
{
InitThreadList();
}
long startTime = DateTime.Now.Ticks;
do
{
//遍历线程列表,找出可用的线程
foreach(MyThread myThread in threadList)
{
//线程为空,需要创建线程
if (myThread.T == null)
{
myThread.Start(waitCallback, obj, false);
return true;
}
else if (myThread.T.ThreadState
==
ThreadState.Suspended)
{//线程为挂起状态,唤醒线程
myThread.Start(waitCallback, obj, true);
return true;
}
}
//在线程 Sleep 前释放锁
Monitor.PulseAll(threadList);
Thread.Sleep(500);
}
while (((DateTime.Now.Ticks
-
startTime) / 10000) < timeOut);
}
finally
{
Monitor.Exit(threadList);
}
}
return false;
}
//使用 MyThread 对象填充线程列表,注意,这个时候线程并没有启动
private static void InitThreadList()
{
threadList = new ArrayList();
for (int i = 0; i < 10; i++)
{
MyThread t = new MyThread();
threadList.Add(t);
}
}
}
}
2.MyThread.cs
using System;
using System.Threading;
namespace CustomThreadPool
{
///<summary>
///封装 .NET 框架提供的 Thread
///</summary>
internal class MyThread
{
//线程
private Thread t;
//委托,这里直接用 .NET 框架自带的,
//也可以根据需要自己定义一个
private WaitCallback w;
//传递给符合委托的回调方法的参数值,
//根据委托的定义而定
private Object o;
///<summary>
///执行回调方法的线程
///</summary>
public Thread T
{
get
{
return t;
}
}
public MyThread()
{
}
///<summary>
///开启新线程或唤醒线程,去执行回调方法
///</summary>
///<param name="w">用回调方法实例化了的委托实例</param>
///<param name="o">传递给回调方法的参数值</param>
///<param name="isSuspend">true 表示线程为挂起状态,
///false 则表示线程还没创建</param>
public void Start(WaitCallback w, Object o, bool isSuspend)
{
//开启新线程或唤醒线程前,先设置
this.w = w;
this.o = o;
//线程为挂起状态,唤醒线程继续执行
if (isSuspend)
{
t.Resume();
}
else
{//线程还没有创建,创建一个新线程,并执行
t = new Thread(new ThreadStart(this.ThreadProc));
t.Start();
}
}
///<summary>
///线程执行的方法
///</summary>
private void ThreadProc()
{
//死循环,使线程唤醒后不是退出,而是继续通过委托执行回调方法
while (true)
{
//通过委托执行回调方法
w(o);
t.Suspend();
}
}
}
}
3.Test.cs
using System;
using System.Threading;
namespace CustomThreadPool
{
///<summary>
///测试自定义线程池
///</summary>
class Test
{
///<summary>
///应用程序的主入口点。
///</summary>
[STAThread]
static void Main(string[] args)
{
//
// TODO: 在此处添加代码以启动应用程序
//
for (int i = 0; i < 5; i++)
{
Console.WriteLine("Start thread {0}", i.ToString());
Thread t = new Thread(new ThreadStart(WorkThread));
t.Start();
}
Console.ReadLine();
Thread.CurrentThread.Abort();
}
public static void WorkThread()
{
for (int i = 0; i < 10; i++)
{
if (i % 2 == 0)
{
if (!ThreadManager.QueueUserWorkItem(
new WaitCallback(ThreadProcOne), i, 2000))
{
Console.WriteLine("Failed" + i.ToString());
}
}
else
{
if (!ThreadManager.QueueUserWorkItem(
new WaitCallback(ThreadProcTwo), i, 2000))
{
Console.WriteLine("Failed" + i.ToString());
}
}
}
Thread.CurrentThread.Abort();
}
public static void ThreadProcOne(Object stateInfo)
{
Console.WriteLine("Test custom threadpool:"
+ ((int)stateInfo).ToString());
}
public static void ThreadProcTwo(Object stateInfo)
{
Console.WriteLine("Change work:"
+ ((int)stateInfo).ToString());
}
}
}