wtf/HashSet.h

   1 /*
   2  * Copyright (C) 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public License
  15  * along with this library; see the file COPYING.LIB.  If not, write to
  16  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA 02110-1301, USA.
  18  *
  19  */
  20
  21 #ifndef WTF_HashSet_h
  22 #define WTF_HashSet_h
  23
  24 #include "FastAllocBase.h"
  25 #include "HashTable.h"
  26
  27 namespace WTF {
  28
  29     template<typename Value, typename HashFunctions, typename Traits> class HashSet;
  30     template<typename Value, typename HashFunctions, typename Traits>
  31     void deleteAllValues(const HashSet<Value, HashFunctions, Traits>&);
  32     template<typename Value, typename HashFunctions, typename Traits>
  33     void fastDeleteAllValues(const HashSet<Value, HashFunctions, Traits>&);
  34
  35     template<typename T> struct IdentityExtractor;
  36
  37     template<typename ValueArg, typename HashArg = typename DefaultHash<ValueArg>::Hash,
  38         typename TraitsArg = HashTraits<ValueArg> > class HashSet : public FastAllocBase {
  39     private:
  40         typedef HashArg HashFunctions;
  41         typedef TraitsArg ValueTraits;
  42
  43     public:
  44         typedef typename ValueTraits::TraitType ValueType;
  45
  46     private:
  47         typedef HashTable<ValueType, ValueType, IdentityExtractor<ValueType>,
  48             HashFunctions, ValueTraits, ValueTraits> HashTableType;
  49
  50     public:
  51         typedef HashTableIteratorAdapter<HashTableType, ValueType> iterator;
  52         typedef HashTableConstIteratorAdapter<HashTableType, ValueType> const_iterator;
  53
  54         void swap(HashSet&);
  55
  56         int size() const;
  57         int capacity() const;
  58         bool isEmpty() const;
  59
  60         iterator begin();
  61         iterator end();
  62         const_iterator begin() const;
  63         const_iterator end() const;
  64
  65         iterator find(const ValueType&);
  66         const_iterator find(const ValueType&) const;
  67         bool contains(const ValueType&) const;
  68
  69         // An alternate version of find() that finds the object by hashing and comparing
  70         // with some other type, to avoid the cost of type conversion. HashTranslator
  71         // must have the following function members:
  72         //   static unsigned hash(const T&);
  73         //   static bool equal(const ValueType&, const T&);
  74         template<typename T, typename HashTranslator> iterator find(const T&);
  75         template<typename T, typename HashTranslator> const_iterator find(const T&) const;
  76         template<typename T, typename HashTranslator> bool contains(const T&) const;
  77
  78         // The return value is a pair of an interator to the new value's location,
  79         // and a bool that is true if an new entry was added.
  80         pair<iterator, bool> add(const ValueType&);
  81
  82         // An alternate version of add() that finds the object by hashing and comparing
  83         // with some other type, to avoid the cost of type conversion if the object is already
  84         // in the table. HashTranslator must have the following function members:
  85         //   static unsigned hash(const T&);
  86         //   static bool equal(const ValueType&, const T&);
  87         //   static translate(ValueType&, const T&, unsigned hashCode);
  88         template<typename T, typename HashTranslator> pair<iterator, bool> add(const T&);
  89
  90         void remove(const ValueType&);
  91         void remove(iterator);
  92         void clear();
  93
  94     private:
  95         friend void deleteAllValues<>(const HashSet&);
  96         friend void fastDeleteAllValues<>(const HashSet&);
  97
  98         HashTableType m_impl;
  99     };
 100
 101     template<typename T> struct IdentityExtractor {
 102         static const T& extract(const T& t) { return t; }
 103     };
 104
 105     template<typename ValueType, typename ValueTraits, typename T, typename Translator>
 106     struct HashSetTranslatorAdapter {
 107         static unsigned hash(const T& key) { return Translator::hash(key); }
 108         static bool equal(const ValueType& a, const T& b) { return Translator::equal(a, b); }
 109         static void translate(ValueType& location, const T& key, const T&, unsigned hashCode)
 110         {
 111             Translator::translate(location, key, hashCode);
 112         }
 113     };
 114
 115     template<typename T, typename U, typename V>
 116     inline void HashSet<T, U, V>::swap(HashSet& other)
 117     {
 118         m_impl.swap(other.m_impl);
 119     }
 120
 121     template<typename T, typename U, typename V>
 122     inline int HashSet<T, U, V>::size() const
 123     {
 124         return m_impl.size();
 125     }
 126
 127     template<typename T, typename U, typename V>
 128     inline int HashSet<T, U, V>::capacity() const
 129     {
 130         return m_impl.capacity();
 131     }
 132
 133     template<typename T, typename U, typename V>
 134     inline bool HashSet<T, U, V>::isEmpty() const
 135     {
 136         return m_impl.isEmpty();
 137     }
 138
 139     template<typename T, typename U, typename V>
 140     inline typename HashSet<T, U, V>::iterator HashSet<T, U, V>::begin()
 141     {
 142         return m_impl.begin();
 143     }
 144
 145     template<typename T, typename U, typename V>
 146     inline typename HashSet<T, U, V>::iterator HashSet<T, U, V>::end()
 147     {
 148         return m_impl.end();
 149     }
 150
 151     template<typename T, typename U, typename V>
 152     inline typename HashSet<T, U, V>::const_iterator HashSet<T, U, V>::begin() const
 153     {
 154         return m_impl.begin();
 155     }
 156
 157     template<typename T, typename U, typename V>
 158     inline typename HashSet<T, U, V>::const_iterator HashSet<T, U, V>::end() const
 159     {
 160         return m_impl.end();
 161     }
 162
 163     template<typename T, typename U, typename V>
 164     inline typename HashSet<T, U, V>::iterator HashSet<T, U, V>::find(const ValueType& value)
 165     {
 166         return m_impl.find(value);
 167     }
 168
 169     template<typename T, typename U, typename V>
 170     inline typename HashSet<T, U, V>::const_iterator HashSet<T, U, V>::find(const ValueType& value) const
 171     {
 172         return m_impl.find(value);
 173     }
 174
 175     template<typename T, typename U, typename V>
 176     inline bool HashSet<T, U, V>::contains(const ValueType& value) const
 177     {
 178         return m_impl.contains(value);
 179     }
 180
 181     template<typename Value, typename HashFunctions, typename Traits>
 182     template<typename T, typename HashTranslator>
 183     typename HashSet<Value, HashFunctions, Traits>::iterator
 184     inline HashSet<Value, HashFunctions, Traits>::find(const T& value)
 185     {
 186         typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;
 187         return m_impl.template find<T, Adapter>(value);
 188     }
 189
 190     template<typename Value, typename HashFunctions, typename Traits>
 191     template<typename T, typename HashTranslator>
 192     typename HashSet<Value, HashFunctions, Traits>::const_iterator
 193     inline HashSet<Value, HashFunctions, Traits>::find(const T& value) const
 194     {
 195         typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;
 196         return m_impl.template find<T, Adapter>(value);
 197     }
 198
 199     template<typename Value, typename HashFunctions, typename Traits>
 200     template<typename T, typename HashTranslator>
 201     inline bool HashSet<Value, HashFunctions, Traits>::contains(const T& value) const
 202     {
 203         typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;
 204         return m_impl.template contains<T, Adapter>(value);
 205     }
 206
 207     template<typename T, typename U, typename V>
 208     pair<typename HashSet<T, U, V>::iterator, bool> HashSet<T, U, V>::add(const ValueType& value)
 209     {
 210         return m_impl.add(value);
 211     }
 212
 213     template<typename Value, typename HashFunctions, typename Traits>
 214     template<typename T, typename HashTranslator>
 215     pair<typename HashSet<Value, HashFunctions, Traits>::iterator, bool>
 216     HashSet<Value, HashFunctions, Traits>::add(const T& value)
 217     {
 218         typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;
 219         return m_impl.template addPassingHashCode<T, T, Adapter>(value, value);
 220     }
 221
 222     template<typename T, typename U, typename V>
 223     inline void HashSet<T, U, V>::remove(iterator it)
 224     {
 225         if (it.m_impl == m_impl.end())
 226             return;
 227         m_impl.internalCheckTableConsistency();
 228         m_impl.removeWithoutEntryConsistencyCheck(it.m_impl);
 229     }
 230
 231     template<typename T, typename U, typename V>
 232     inline void HashSet<T, U, V>::remove(const ValueType& value)
 233     {
 234         remove(find(value));
 235     }
 236
 237     template<typename T, typename U, typename V>
 238     inline void HashSet<T, U, V>::clear()
 239     {
 240         m_impl.clear();
 241     }
 242
 243     template<typename ValueType, typename HashTableType>
 244     void deleteAllValues(HashTableType& collection)
 245     {
 246         typedef typename HashTableType::const_iterator iterator;
 247         iterator end = collection.end();
 248         for (iterator it = collection.begin(); it != end; ++it)
 249             delete *it;
 250     }
 251
 252     template<typename T, typename U, typename V>
 253     inline void deleteAllValues(const HashSet<T, U, V>& collection)
 254     {
 255         deleteAllValues<typename HashSet<T, U, V>::ValueType>(collection.m_impl);
 256     }
 257
 258     template<typename ValueType, typename HashTableType>
 259     void fastDeleteAllValues(HashTableType& collection)
 260     {
 261         typedef typename HashTableType::const_iterator iterator;
 262         iterator end = collection.end();
 263         for (iterator it = collection.begin(); it != end; ++it)
 264             fastDelete(*it);
 265     }
 266
 267     template<typename T, typename U, typename V>
 268     inline void fastDeleteAllValues(const HashSet<T, U, V>& collection)
 269     {
 270         fastDeleteAllValues<typename HashSet<T, U, V>::ValueType>(collection.m_impl);
 271     }
 272
 273     template<typename T, typename U, typename V, typename W>
 274     inline void copyToVector(const HashSet<T, U, V>& collection, W& vector)
 275     {
 276         typedef typename HashSet<T, U, V>::const_iterator iterator;
 277
 278         vector.resize(collection.size());
 279
 280         iterator it = collection.begin();
 281         iterator end = collection.end();
 282         for (unsigned i = 0; it != end; ++it, ++i)
 283             vector[i] = *it;
 284     }
 285
 286 } // namespace WTF
 287
 288 using WTF::HashSet;
 289
 290 #endif /* WTF_HashSet_h */