xpcom/glue/nsClassHashtable.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is C++ hashtable templates.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Benjamin Smedberg.
  19  * Portions created by the Initial Developer are Copyright (C) 2002
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either the GNU General Public License Version 2 or later (the "GPL"), or
  26  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
  28  * of those above. If you wish to allow use of your version of this file only
  29  * under the terms of either the GPL or the LGPL, and not to allow others to
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  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #ifndef nsClassHashtable_h__
  39 #define nsClassHashtable_h__
  40
  41 #include "nsBaseHashtable.h"
  42 #include "nsHashKeys.h"
  43 #include "nsAutoPtr.h"
  44
  45 /**
  46  * templated hashtable class maps keys to C++ object pointers.
  47  * See nsBaseHashtable for complete declaration.
  48  * @param KeyClass a wrapper-class for the hashtable key, see nsHashKeys.h
  49  *   for a complete specification.
  50  * @param Class the class-type being wrapped
  51  * @see nsInterfaceHashtable, nsClassHashtable
  52  */
  53 template<class KeyClass,class T>
  54 class nsClassHashtable :
  55   public nsBaseHashtable< KeyClass, nsAutoPtr<T>, T* >
  56 {
  57 public:
  58   typedef typename KeyClass::KeyType KeyType;
  59   typedef T* UserDataType;
  60
  61   /**
  62    * @copydoc nsBaseHashtable::Get
  63    * @param pData if the key doesn't exist, pData will be set to nsnull.
  64    */
  65   PRBool Get(KeyType aKey, UserDataType* pData) const;
  66 };
  67
  68
  69 /**
  70  * Thread-safe version of nsClassHashtable
  71  * @param KeyClass a wrapper-class for the hashtable key, see nsHashKeys.h
  72  *   for a complete specification.
  73  * @param Class the class-type being wrapped
  74  * @see nsInterfaceHashtable, nsClassHashtable
  75  */
  76 template<class KeyClass,class T>
  77 class nsClassHashtableMT :
  78   public nsBaseHashtableMT< KeyClass, nsAutoPtr<T>, T* >
  79 {
  80 public:
  81   typedef typename KeyClass::KeyType KeyType;
  82   typedef T* UserDataType;
  83
  84   /**
  85    * @copydoc nsBaseHashtable::Get
  86    * @param pData if the key doesn't exist, pData will be set to nsnull.
  87    */
  88   PRBool Get(KeyType aKey, UserDataType* pData) const;
  89 };
  90
  91
  92 //
  93 // nsClassHashtable definitions
  94 //
  95
  96 template<class KeyClass,class T>
  97 PRBool
  98 nsClassHashtable<KeyClass,T>::Get(KeyType aKey, T** retVal) const
  99 {
 100   typename nsBaseHashtable<KeyClass,nsAutoPtr<T>,T*>::EntryType* ent =
 101     GetEntry(aKey);
 102
 103   if (ent)
 104   {
 105     if (retVal)
 106       *retVal = ent->mData;
 107
 108     return PR_TRUE;
 109   }
 110
 111   if (retVal)
 112     *retVal = nsnull;
 113
 114   return PR_FALSE;
 115 }
 116
 117
 118 //
 119 // nsClassHashtableMT definitions
 120 //
 121
 122 template<class KeyClass,class T>
 123 PRBool
 124 nsClassHashtableMT<KeyClass,T>::Get(KeyType aKey, T** retVal) const
 125 {
 126   PR_Lock(this->mLock);
 127
 128   typename nsBaseHashtableMT<KeyClass,nsAutoPtr<T>,T*>::EntryType* ent =
 129     GetEntry(aKey);
 130
 131   if (ent)
 132   {
 133     if (retVal)
 134       *retVal = ent->mData;
 135
 136     PR_Unlock(this->mLock);
 137
 138     return PR_TRUE;
 139   }
 140
 141   if (retVal)
 142     *retVal = nsnull;
 143
 144   PR_Unlock(this->mLock);
 145
 146   return PR_FALSE;
 147 }
 148
 149 #endif // nsClassHashtable_h__