一、吐槽
ThreadLocal<T>明显是.NET从JAVA中来的一个概念,但是这种设计是否出现了问题.
很明显,在JAVA中threadLocal直接是Thread的成员,当然随着thread这个宿主而存在.
但.NET中对于ThreadLocal<T>的设计明显独立于Thread之外(当然你可以说内部有关联)
,起最终结果是ThreadLocal<T>所产生的对象不会随着线程的终止而释放.
二、问题代码
/*
* 由SharpDevelop创建。
* 用户： qsmy
* 日期: 2016/12/31
* 时间: 9:31
*
* 要改变这种模板请点击 工具|选项|代码编写|编辑标准头文件
*/
using System;
using System.Threading; namespace ThreadLocalTest
{
public class MyObject
{
public static readonly ThreadLocal<MyObject> threadLocal
= new ThreadLocal<MyObject>(true); public static MyObject GetCurrentThreadMyObject(String name)
{
if (threadLocal.Value == null) {
threadLocal.Value = new MyObject(name);
}
return threadLocal.Value;
} String _name;
public byte[] _bs;
public MyObject(String name)
{
_name = name;
Console.WriteLine("创建MyObject.name=" + name);
_bs=new byte[(1024*1024*500)];
for (int i = 0; i < _bs.Length; i++) {
_bs[i]=3;
}
}
~MyObject()
{
Console.WriteLine("析构MyObject.name=" + _name);
}
public void Dispose()
{
threadLocal.Value = null;
threadLocal.Values.Clear();
//Console.WriteLine(MyObject.threadLocal.Values.Count);
}
}
class Program
{ public static void Main(string[] args)
{ Thread th1 = new Thread((state) => {
var obj = MyObject.GetCurrentThreadMyObject("obj1");
obj.ToString();
Console.WriteLine("t1.id=" + Thread.CurrentThread.ManagedThreadId); obj.Dispose();
Thread.CurrentThread.Abort();
});
th1.Start(); Thread th2 = new Thread((state) => {
var obj = MyObject.GetCurrentThreadMyObject("obj2");
obj.ToString();
Console.WriteLine("t2.id=" + Thread.CurrentThread.ManagedThreadId);
obj.Dispose();
Thread.CurrentThread.Abort();
});
th2.Start(); Thread.Sleep(20000);
Console.WriteLine(th1.ThreadState); Console.ReadKey(true);
}
}
}
四、运行结果内存不释
哪位大侠对此有深入研究,求赐教.