static async Task ProcessAsync()
{
var unsafeState = new UnsafeState();
Task[] tasks = new Task[4];
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(unsafeState));
}
await Task.WhenAll(tasks);
WriteLine("---------------------------------------");
var firstState = new DoubleCheckedLocking();
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(firstState));
}
await Task.WhenAll(tasks);
WriteLine("---------------------------------------");
var secondState = new BCLDoubleChecked();
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(secondState));
}
await Task.WhenAll(tasks);
WriteLine("---------------------------------------");
var lazy = new Lazy <ValueToAccess>(Compute);
var thirdState = new LazyWrapper(lazy);
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(thirdState));
}
await Task.WhenAll(tasks);
WriteLine("---------------------------------------");
var fourthState = new BCLThreadSafeFactory();
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(fourthState));
}
await Task.WhenAll(tasks);
WriteLine("---------------------------------------");
}
static async Task ProcessAsynchronously()
{
// 不安全的对象，构造方法会被调用了多次，
// 并且不同的线程中值是不同的
var unsafeState = new UnsafeState();
Task[] tasks = new Task[4];
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(unsafeState));
}
await Task.WhenAll(tasks);
Console.WriteLine("------------------------------");
// 使用双重锁定模式
var firstState = new DoubleCheckedLocking();
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(firstState));
}
await Task.WhenAll(tasks);
Console.WriteLine("------------------------------");
// 使用LazyInitializer.EnsureInitialized方法
var secondState = new BCLDoubleChecked();
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(secondState));
}
await Task.WhenAll(tasks);
Console.WriteLine("------------------------------");
// 使用Lazy<T>类型
var lazy = new Lazy <ValueToAccess>(Compute);
var thirdState = new LazyWrapper(lazy);
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(thirdState));
}
await Task.WhenAll(tasks);
Console.WriteLine("------------------------------");
// 使用LazyInitializer.EnsureInitialized方法的一个不使用锁的重载
var fourthState = new BCLThreadSafeFactory();
for (int i = 0; i < 4; i++)
{
tasks[i] = Task.Run(() => Worker(fourthState));
}
await Task.WhenAll(tasks);
Console.WriteLine("------------------------------");
}