/// <summary>
/// 讲对象添加到队列中
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
public virtual bool Enqueue(T value)
{
var newTail = new MpscLinkedQueueNode <T>()
{
Value = value, Next = null
};
//F0：1将tail修改为newTail
var oldTail = GetAndSetTailByCAS(newTail);
//F1：2将oldTail的Next修改为newTail
oldTail.Next = newTail;
return(true);
}
/// <summary>
/// 从队列中取出一个项
/// </summary>
/// <returns></returns>
/// <remarks>
/// 该方法只适合单个消费者
/// </remarks>
public virtual T Dequeue()
{
var next = PeekNode();
if (next == null)
{
return(null);
}
this.head.Next = next.Next;
if (this.tail == next)
{
this.tail = this.head;
}
return(next.Value);
}
/// <summary>
/// 适合多个生产者一个消费者的单向队列
/// </summary>
public MpscLinkedQueue()
{
head = tail = defaultNode;
}
/// <summary>
/// 获取并设置Tail,该操作是原子操作
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
private MpscLinkedQueueNode <T> GetAndSetTailByCAS(MpscLinkedQueueNode <T> value)
{
return(Interlocked.Exchange(ref this.tail, value));
}