Concurrent Object Pool, the Right Way

#region Copyright (c) 2012 Roman Atachiants
/*************************************************************************
 * 
 * Copyright (C) 2012 Roman Atachiants
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a 
 * copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation 
 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the 
 * Software is furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included 
 * in all copies or substantial portions of the Software.
 * 
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 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
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#endregion

using System;
using System.Collections.Generic;
using System.Text;

namespace ObjectPool
{
    /// <summary>
    /// Defines a contract for an object pool.
    /// </summary>
    public interface IRecycler
    {
        /// <summary>
        /// Acquires an instance of a recyclable object
        /// </summary>
        /// <returns></returns>
        IRecyclable Acquire();

        /// <summary>
        /// Releases an instance of a recyclable object back to the pool.
        /// </summary>
        /// <param name="instance">The instance of IRecyclable to release.</param>
        void Release(IRecyclable instance);

        /// <summary>
        /// Gets the overall number of elements managed by this pool.
        /// </summary>
        int Count { get; }

        /// <summary>
        /// Gets the number of available elements currently contained in the pool.
        /// </summary>
        int AvailableCount {get;}

        /// <summary>
        /// Gets the number of elements currently in use and not available in this pool.
        /// </summary>
        int InUseCount {get;}

    }

    /// <summary>
    /// Defines a contract for an object pool.
    /// </summary>
    public interface IRecycler<T> : IRecycler
        where T : class, IRecyclable
    {
        /// <summary>
        /// Acquires an instance of a recyclable object
        /// </summary>
        /// <returns></returns>
        new T Acquire();

        /// <summary>
        /// Releases an instance of a recyclable object back to the pool.
        /// </summary>
        /// <param name="instance">The instance of IRecyclable to release.</param>
        void Release(T instance);
    }

}