有趣的多线程编程（4）——死锁[1]

// DeadLockSample.cs
// 分析一下为什么会发生死锁？

using System;
using System.Threading;

public class Test
{
    static readonly object firstLock = new object();
    static readonly object secondLock = new object();
    
    static void Main()
    {
        new Thread(new ThreadStart(ThreadJob)).Start();
        
        // Wait until we're fairly sure the other thread
        // has grabbed firstLock
        Thread.Sleep(500);
        
        Console.WriteLine ("Locking secondLock");
        lock (secondLock)
        {
            Console.WriteLine ("Locked secondLock");
            Console.WriteLine ("Locking firstLock");
            lock (firstLock)
            {
                Console.WriteLine ("Locked firstLock");
            }
            Console.WriteLine ("Released firstLock");
        }
        Console.WriteLine("Released secondLock");
    }
    
    static void ThreadJob()
    {
        Console.WriteLine ("\t\t\t\tLocking firstLock");
        lock (firstLock)
        {
            Console.WriteLine("\t\t\t\tLocked firstLock");
            // Wait until we're fairly sure the first thread
            // has grabbed secondLock
            Thread.Sleep(1000);
            Console.WriteLine("\t\t\t\tLocking secondLock");
            lock (secondLock)
            {
                Console.WriteLine("\t\t\t\tLocked secondLock");
            }
            Console.WriteLine ("\t\t\t\tReleased secondLock");
        }
        Console.WriteLine("\t\t\t\tReleased firstLock");
    }
}

                                Locking firstLock

                                Locked firstLock

Locking secondLock

Locked secondLock

Locking firstLock
                                Locking secondLock