Facilities/Cache/Castle.Facilities.Cache.Tests/FifoCacheManager.cs

   1 // Copyright 2004-2008 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.Facilities.Cache.Tests
  16 {
  17         using System.Collections;
  18         using System.Collections.Specialized;
  19         using Castle.Facilities.Cache.Manager;
  20
  21         /// <summary>
  22         /// Description résumée de FifoCacheManager.
  23         /// </summary>
  24         public class FifoCacheManager : ICacheManager
  25         {
  26                 #region Fields
  27                 private int _cacheSize = 0;
  28                 private IDictionary _cache = null;
  29                 private IList _keyList = null;
  30                 private ICacheKeyGenerator _cacheKeyGenerator = null;
  31                 #endregion
  32
  33                 public IList KeyList
  34                 {
  35                         get { return _keyList; }
  36                 }
  37
  38                 #region Constructor (s) / Destructor
  39                 /// <summary>
  40                 ///
  41                 /// </summary>
  42                 public FifoCacheManager(int cacheSize)
  43                 {
  44                         _cacheSize = cacheSize;
  45                         _cache = new HybridDictionary();
  46                         _keyList = new ArrayList();
  47                 }
  48                 #endregion
  49
  50                 #region ICacheManager Members
  51
  52                 /// <summary>
  53                 /// A generator of keys for a cache entry.
  54                 /// </summary>
  55                 public ICacheKeyGenerator CacheKeyGenerator
  56                 {
  57                         get { return _cacheKeyGenerator; }
  58                         set { _cacheKeyGenerator = value; }
  59                 }
  60
  61                 /// <summary>
  62                 /// Clears all elements from the cache.
  63                 /// </summary>
  64                 public void Clear()
  65                 {
  66                         lock(this)
  67                         {
  68                                 _cache.Clear();
  69                                 _keyList.Clear();
  70                         }
  71                 }
  72
  73
  74                 /// <summary>
  75                 /// Adds an item with the specified key and value into cached data.
  76                 /// Gets a cached object with the specified key.
  77                 /// </summary>
  78                 /// <value>The cached object or <c>null</c></value>
  79                 public object this [object key]
  80                 {
  81                         get
  82                         {
  83                                 lock (this)
  84                                 {
  85                                         return _cache[key];
  86                                 }
  87                         }
  88                         set
  89                         {
  90                                 lock (this)
  91                                 {
  92                                         _cache.Add(key, value);
  93                                         _keyList.Add(key);
  94                                         if (_keyList.Count > _cacheSize)
  95                                         {
  96                                                 object oldestKey = _keyList[0];
  97                                                 _keyList.Remove(0);
  98                                                 _cache.Remove(oldestKey);
  99                                         }
 100                                 }
 101                         }
 102                 }
 103
 104                 #endregion
 105
 106         }
 107 }