mcs/class/System/System.Collections.Specialized/HybridDictionary.cs

   1 //\r
   2 // System.Collections.Specialized.HybridDictionary.cs\r
   3 //\r
   4 // Author:\r
   5 //   Lawrence Pit (loz@cable.a2000.nl)
   6 //
   7 // Copyright (C) 2004 Novell (http://www.novell.com)\r
   8 //\r
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30 \r
  31 using System;\r
  32 using System.Collections;\r
  33 \r
  34 namespace System.Collections.Specialized {\r
  35         \r
  36         [Serializable]\r
  37         public class HybridDictionary : IDictionary, ICollection, IEnumerable {\r
  38                 \r
  39                 private const int switchAfter = 10;\r
  40 \r
  41                 private ListDictionary list;\r
  42                 private Hashtable hashtable;\r
  43                 private bool caseInsensitive = false;\r
  44 \r
  45                 // Constructors\r
  46                 \r
  47                 public HybridDictionary() : this (0, false) { }\r
  48                 \r
  49                 public HybridDictionary (bool caseInsensitive) : this (0, caseInsensitive) { }\r
  50                 \r
  51                 public HybridDictionary (int initialSize) : this (initialSize, false) { }\r
  52                 \r
  53                 public HybridDictionary(int initialSize, bool caseInsensitive) \r
  54                 {\r
  55                         this.caseInsensitive = caseInsensitive;\r
  56                 \r
  57                         if (initialSize <= switchAfter)\r
  58                                 if (caseInsensitive)\r
  59                                         list = new ListDictionary (CaseInsensitiveComparer.Default);\r
  60                                 else\r
  61                                         list = new ListDictionary ();\r
  62                         else\r
  63                                 if (caseInsensitive) \r
  64                                         hashtable = new Hashtable (initialSize, \r
  65                                                         CaseInsensitiveHashCodeProvider.Default, \r
  66                                                         CaseInsensitiveComparer.Default);\r
  67                                 else\r
  68                                         hashtable = new Hashtable (initialSize);\r
  69                 }               \r
  70 \r
  71                 \r
  72                 // Properties\r
  73                 \r
  74                 public int Count {\r
  75                         get {\r
  76                                 if (list != null)\r
  77                                         return list.Count;\r
  78                                 return hashtable.Count;\r
  79                         }\r
  80                 }\r
  81                 \r
  82                 public bool IsFixedSize {\r
  83                         get { return false; }\r
  84                 }\r
  85                 \r
  86                 public bool IsReadOnly {\r
  87                         get { return false; }\r
  88                 }\r
  89                 \r
  90                 public bool IsSynchronized {\r
  91                         get { return false; }\r
  92                 }\r
  93                 \r
  94                 public object this [object key] {\r
  95                         get { \r
  96                                 if (key == null)\r
  97                                         throw new ArgumentNullException("key");\r
  98                                 if (list != null)\r
  99                                         return list [key];\r
 100                                 return hashtable [key];\r
 101                         }\r
 102                         set { \r
 103                                 if (list != null)\r
 104                                         if (list.Count >= switchAfter) \r
 105                                                 Switch ();\r
 106                                         else {\r
 107                                                 list [key] = value;\r
 108                                                 return;\r
 109                                         }\r
 110                                 hashtable [key] = value;\r
 111                         }\r
 112                 }\r
 113                 \r
 114                 public ICollection Keys {\r
 115                         get {\r
 116                                 if (list != null)\r
 117                                         return list.Keys;\r
 118                                 return hashtable.Keys;\r
 119                         }\r
 120                 }\r
 121                 \r
 122                 public object SyncRoot {\r
 123                         get { return this; }\r
 124                 }\r
 125                 \r
 126                 public ICollection Values {\r
 127                         get { \r
 128                                 if (list != null)\r
 129                                         return list.Values;\r
 130                                 return hashtable.Values;\r
 131                         }\r
 132                 }\r
 133                 \r
 134                 \r
 135                 // Methods\r
 136                 \r
 137                 public void Add (object key, object value) \r
 138                 {\r
 139                         if (list != null)\r
 140                                 if (list.Count >= switchAfter) \r
 141                                         Switch ();\r
 142                                 else {\r
 143                                         list.Add (key, value);\r
 144                                         return;\r
 145                                 }\r
 146                         hashtable.Add (key, value);\r
 147                 }\r
 148                 \r
 149                 public void Clear ()\r
 150                 {\r
 151                         if (caseInsensitive)\r
 152                                 list = new ListDictionary (CaseInsensitiveComparer.Default);\r
 153                         else\r
 154                                 list = new ListDictionary ();\r
 155                         hashtable = null;\r
 156                 }\r
 157                 \r
 158                 public bool Contains (object key)\r
 159                 {
 160                         if (key == null) {
 161                                 if (this.Count == 0)
 162                                         return false;
 163                                 else
 164                                         throw new ArgumentNullException ("key");\r
 165                         }
 166                         if (list != null)\r
 167                                 return list.Contains (key);\r
 168                         return hashtable.Contains (key);\r
 169                 }\r
 170                 \r
 171                 public void CopyTo (Array array, int index)\r
 172                 {\r
 173                         if (list != null) \r
 174                                 list.CopyTo (array, index);\r
 175                         else\r
 176                                 hashtable.CopyTo (array, index);\r
 177                 }\r
 178                 \r
 179                 public IDictionaryEnumerator GetEnumerator ()\r
 180                 {\r
 181                         if (list != null)\r
 182                                 return list.GetEnumerator ();\r
 183                         return hashtable.GetEnumerator ();\r
 184                 }\r
 185 \r
 186                 IEnumerator IEnumerable.GetEnumerator ()\r
 187                 {\r
 188                         return GetEnumerator ();\r
 189                 }\r
 190 \r
 191                 public void Remove (object key)\r
 192                 {\r
 193                         if (list != null)\r
 194                                 list.Remove (key);\r
 195                         else    \r
 196                                 hashtable.Remove (key);\r
 197                 }\r
 198                 \r
 199                 private void Switch ()\r
 200                 {\r
 201                         if (caseInsensitive) \r
 202                                 hashtable = new Hashtable (switchAfter + 1,\r
 203                                                         CaseInsensitiveHashCodeProvider.Default, \r
 204                                                         CaseInsensitiveComparer.Default);\r
 205                         else\r
 206                                 hashtable = new Hashtable (switchAfter + 1);\r
 207                         IDictionaryEnumerator e = list.GetEnumerator ();\r
 208                         while (e.MoveNext ())\r
 209                                 hashtable.Add (e.Key, e.Value);\r
 210                         list = null;\r
 211                 }\r
 212         }\r
 213 }\r