FixedSizedQueue

FixedSizedQueue.cs

namespace Sample
{
    using System.Collections.Concurrent;

    public class FixedSizedQueue<T>
    {
        ConcurrentQueue<T> q = new ConcurrentQueue<T>();

        public int Limit { get; internal set; }

        public FixedSizedQueue(int limit)
        {
            Limit = limit;
        }

        public void Enqueue(T obj)
        {
            q.Enqueue(obj);
            lock (this)
            {
                T overflow;
                while (q.Count > Limit && q.TryDequeue(out overflow)) ;
            }
        }

        public T[] DequeueAll()
        {
            var returnValue = new T[q.Count];

            lock (this)
            {
                int i = 0;
                T item;
                while (q.TryDequeue(out item))
                {
                    returnValue[i] = item;
                    ++i;
                };
            }

            return returnValue;
        }
    }
}