OpenSim-Test/OpenSim/Framework/Pool.cs

/*
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 * See CONTRIBUTORS.TXT for a full list of copyright holders.
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 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

using System;
using System.Collections.Generic;

namespace OpenSim.Framework
{
    /// <summary>
    /// Naive pool implementation.
    /// </summary>
    /// <remarks>
    /// Currently assumes that objects are in a useable state when returned.
    /// </remarks>
    public class Pool<T>
    {
        /// <summary>
        /// Number of objects in the pool.
        /// </summary>
        public int Count
        {
            get
            {
                lock (m_pool)
                    return m_pool.Count;
            }
        }

        private Stack<T> m_pool;

        /// <summary>
        /// Maximum pool size.  Beyond this, any returned objects are not pooled.
        /// </summary>
        private int m_maxPoolSize;

        private Func<T> m_createFunction;

        public Pool(Func<T> createFunction, int maxSize)
        {
            m_maxPoolSize = maxSize;
            m_createFunction = createFunction;
            m_pool = new Stack<T>(m_maxPoolSize);
        }

        public T GetObject()
        {
            lock (m_pool)
            {
                if (m_pool.Count > 0)
                    return m_pool.Pop();
                else
                    return m_createFunction();
            }
        }

        public void ReturnObject(T obj)
        {
            lock (m_pool)
            {
                if (m_pool.Count >= m_maxPoolSize)
                    return;
                else
                    m_pool.Push(obj);
            }
        }
    }
}