Java多线程下解决资源竞争的7种方法详解

private static object obj = new object();
  private static int lockInt;
  private static void LockIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    lock (obj)
    {
     lockInt++;
    }
   }
  }

private static Mutex mutex = new Mutex();
  private static int mutexInt;
  private static void MutexIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    mutex.WaitOne();
    mutexInt++;
    mutex.ReleaseMutex();
   }
  }

private static Semaphore sema = new Semaphore(1, 1);
  private static int semaphoreInt;
  private static void SemaphoreIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    sema.WaitOne();
    semaphoreInt++;
    sema.Release();
   }
  }

public static AutoResetEvent autoResetEvent = new AutoResetEvent(true);
  private static int autoResetEventInt;
  private static void AutoResetEventIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    if (autoResetEvent.WaitOne())
    {
     autoResetEventInt++;
     autoResetEvent.Set();
    }
   }
  }

private static ReaderWriterLockSlim LockSlim = new ReaderWriterLockSlim();
  private static int lockSlimInt;
  private static void LockSlimIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    LockSlim.EnterWriteLock();
    lockSlimInt++;
    LockSlim.ExitWriteLock();
   }
  }

private static int isLock;
  private static int ceInt;
  private static void CEIntAdd()
  {
   //long tmp = 0;
   for (var i = 0; i < runTimes; i++)
   {
    while (Interlocked.CompareExchange(ref isLock, 1, 0) == 1) { Thread.Sleep(1); }

    ceInt++;
    Interlocked.Exchange(ref isLock, 0);
   }
  }

private static int atomicInt;
  private static void AtomicIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    Interlocked.Increment(ref atomicInt);
   }
  }

private static int noLockInt;
  private static void NoLockIntAdd()
  {
   for (var i = 0; i < runTimes; i++)
   {
    noLockInt++;
   }
  }

private static void Run()
  {
   var stopwatch = new Stopwatch();
   var taskList = new Task[loopTimes];

   // 多线程
   Console.WriteLine();
   Console.WriteLine($"    线程数:{loopTimes}");
   Console.WriteLine($"   执行次数:{runTimes}");
   Console.WriteLine($"  校验值应等于:{runTimes * loopTimes}");

   // AtomicIntAdd
   stopwatch.Restart();
   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { AtomicIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("AtomicIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{atomicInt}");

   // CEIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { CEIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("CEIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{ceInt}");

   // LockIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { LockIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("LockIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{lockInt}");

   // MutexIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { MutexIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("MutexIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{mutexInt}");

   // LockSlimIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { LockSlimIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("LockSlimIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{lockSlimInt}");

   // SemaphoreIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { SemaphoreIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("SemaphoreIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{semaphoreInt}");


   // AutoResetEventIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { AutoResetEventIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("AutoResetEventIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{autoResetEventInt}");

   // NoLockIntAdd
   taskList = new Task[loopTimes];
   stopwatch.Restart();

   for (var i = 0; i < loopTimes; i++)
   {
    taskList[i] = Task.Factory.StartNew(() => { NoLockIntAdd(); });
   }
   Task.WaitAll(taskList);
   Console.WriteLine($"{GetFormat("NoLockIntAdd")}, 总耗时:{stopwatch.ElapsedMilliseconds}毫秒, 校验值:{noLockInt}");
   Console.WriteLine();
  }