CnmSynchronizedCache.cs

Go to the documentation of this file.

/*
 * Copyright (c) Contributors, http://opensimulator.org/
 * See CONTRIBUTORS.TXT for a full list of copyright holders.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the OpenSimulator Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       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
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

using System;
using System.Collections;
using System.Collections.Generic;
using System.Threading;

namespace OpenSim.Framework
{
    public class CnmSynchronizedCache<TKey, TValue> : ICnmCache<TKey, TValue>
    {
        private readonly ICnmCache<TKey, TValue> m_cache;

        private readonly object m_syncRoot;

        private CnmSynchronizedCache(ICnmCache<TKey, TValue> cache)
        {
            m_cache = cache;
            m_syncRoot = m_cache.SyncRoot;
        }

        public static ICnmCache<TKey, TValue> Synchronized(ICnmCache<TKey, TValue> cache)
        {
            if (cache == null)
                throw new ArgumentNullException("cache");
            return cache.IsSynchronized ? cache : new CnmSynchronizedCache<TKey, TValue>(cache);
        }

        #region Nested type: SynchronizedEnumerator

        private class SynchronizedEnumerator : IEnumerator<KeyValuePair<TKey, TValue>>
        {
            private readonly IEnumerator<KeyValuePair<TKey, TValue>> m_enumerator;

            private object m_syncRoot;

            public SynchronizedEnumerator(IEnumerator<KeyValuePair<TKey, TValue>> enumerator, object syncRoot)
            {
                m_syncRoot = syncRoot;
                m_enumerator = enumerator;
                Monitor.Enter(m_syncRoot);
            }

            ~SynchronizedEnumerator()
            {
                Dispose();
            }

            #region IEnumerator<KeyValuePair<TKey,TValue>> Members

            public KeyValuePair<TKey, TValue> Current
            {
                get { return m_enumerator.Current; }
            }

            object IEnumerator.Current
            {
                get { return Current; }
            }

            public void Dispose()
            {
                if (m_syncRoot != null)
                {
                    Monitor.Exit(m_syncRoot);
                    m_syncRoot = null;
                }

                m_enumerator.Dispose();
                GC.SuppressFinalize(this);
            }

            public bool MoveNext()
            {
                return m_enumerator.MoveNext();
            }

            public void Reset()
            {
                m_enumerator.Reset();
            }

            #endregion
        }

        #endregion

        #region ICnmCache<TKey,TValue> Members

        public int Count
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.Count;
                }
            }
        }

        public TimeSpan ExpirationTime
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.ExpirationTime;
                }
            }

            set
            {
                lock (m_syncRoot)
                {
                    m_cache.ExpirationTime = value;
                }
            }
        }

        public bool IsCountLimited
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.IsCountLimited;
                }
            }
        }

        public bool IsSizeLimited
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.IsSizeLimited;
                }
            }
        }

        public bool IsSynchronized
        {
            get { return true; }
        }

        public bool IsTimeLimited
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.IsTimeLimited;
                }
            }
        }

        public int MaxCount
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.MaxCount;
                }
            }

            set
            {
                lock (m_syncRoot)
                {
                    m_cache.MaxCount = value;
                }
            }
        }

        public long MaxElementSize
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.MaxElementSize;
                }
            }
        }

        public long MaxSize
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.MaxSize;
                }
            }

            set
            {
                lock (m_syncRoot)
                {
                    m_cache.MaxSize = value;
                }
            }
        }

        public long Size
        {
            get
            {
                lock (m_syncRoot)
                {
                    return m_cache.Size;
                }
            }
        }

        public object SyncRoot
        {
            get { return m_syncRoot; }
        }

        public void Clear()
        {
            lock (m_syncRoot)
            {
                m_cache.Clear();
            }
        }

        public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
        {
            lock (m_syncRoot)
            {
                return new SynchronizedEnumerator(m_cache.GetEnumerator(), m_syncRoot);
            }
        }

        public void PurgeExpired()
        {
            lock (m_syncRoot)
            {
                m_cache.PurgeExpired();
            }
        }

        public void Remove(TKey key)
        {
            lock (m_syncRoot)
            {
                m_cache.Remove(key);
            }
        }

        public void RemoveRange(IEnumerable<TKey> keys)
        {
            lock (m_syncRoot)
            {
                m_cache.RemoveRange(keys);
            }
        }

        public bool Set(TKey key, TValue value, long size)
        {
            lock (m_syncRoot)
            {
                return m_cache.Set(key, value, size);
            }
        }

        public bool TryGetValue(TKey key, out TValue value)
        {
            lock (m_syncRoot)
            {
                return m_cache.TryGetValue(key, out value);
            }
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

        #endregion
    }
}