lemon/bits/vector_map.h
author deba
Fri, 14 Oct 2005 10:48:34 +0000
changeset 1719 674182524bd9
parent 1703 eb90e3d6bddc
child 1730 fffa6456548a
permissions -rw-r--r--
Traits moved to own file
Tag for reference maps
Possibility to handle proper the return type
of the operator[]() const -- value or reference
     1 /* -*- C++ -*-
     2  * lemon/vector_map.h - Part of LEMON, a generic C++ optimization library
     3  *
     4  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     5  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     6  *
     7  * Permission to use, modify and distribute this software is granted
     8  * provided that this copyright notice appears in all copies. For
     9  * precise terms see the accompanying LICENSE file.
    10  *
    11  * This software is provided "AS IS" with no warranty of any kind,
    12  * express or implied, and with no claim as to its suitability for any
    13  * purpose.
    14  *
    15  */
    16 
    17 #ifndef LEMON_VECTOR_MAP_H
    18 #define LEMON_VECTOR_MAP_H
    19 
    20 #include <vector>
    21 #include <algorithm>
    22 
    23 #include <lemon/utility.h>
    24 #include <lemon/bits/map_iterator.h>
    25 #include <lemon/bits/alteration_notifier.h>
    26 #include <lemon/concept_check.h>
    27 #include <lemon/concept/maps.h>
    28 
    29 /// \ingroup graphmapfactory
    30 ///
    31 ///\file
    32 ///\brief Vector based graph maps.
    33 
    34 namespace lemon {
    35 
    36   /// \ingroup graphmapfactory
    37   ///
    38   /// \brief Graph map based on the std::vector storage.
    39   ///
    40   /// The VectorMap template class is graph map structure what
    41   /// automatically updates the map when a key is added to or erased from
    42   /// the map. This map factory uses the allocators to implement 
    43   /// the container functionality. This map factory
    44   /// uses the std::vector to implement the container function.
    45   ///
    46   /// \param Registry The AlterationNotifier that will notify this map.
    47   /// \param Item The item type of the graph items.
    48   /// \param Value The value type of the map.
    49   /// 
    50   /// \author Balazs Dezso
    51   	
    52   template <
    53     typename _Graph, 
    54     typename _Item,    
    55     typename _Value
    56     >
    57   class VectorMap : public AlterationNotifier<_Item>::ObserverBase {
    58   private:
    59 		
    60     /// The container type of the map.
    61     typedef std::vector<_Value> Container;	
    62 
    63   public:
    64 
    65     /// The graph type of the map. 
    66     typedef _Graph Graph;
    67     /// The reference map tag.
    68     typedef True ReferenceMapTag;
    69 
    70     /// The key type of the map.
    71     typedef _Item Key;
    72     /// The value type of the map.
    73     typedef _Value Value;
    74     /// The const reference type of the map.
    75     typedef typename Container::const_reference ConstReference;
    76     /// The reference type of the map.
    77     typedef typename Container::reference Reference;
    78 
    79     typedef const Value ConstValue;
    80     typedef Value* Pointer;
    81     typedef const Value* ConstPointer;
    82 
    83     typedef AlterationNotifier<_Item> Registry;
    84 
    85     /// The map type.
    86     typedef VectorMap Map;
    87     /// The base class of the map.
    88     typedef typename Registry::ObserverBase Parent;
    89 
    90     /// The reference type of the map;
    91     typedef typename Container::reference Reference;
    92     /// The pointer type of the map;
    93     typedef typename Container::pointer Pointer;
    94 
    95     /// The const value type of the map.
    96     typedef const Value ConstValue;
    97     /// The const reference type of the map;
    98     typedef typename Container::const_reference ConstReference;
    99     /// The pointer type of the map;
   100     typedef typename Container::const_pointer ConstPointer;
   101 
   102     typedef True FullTypeTag;
   103 
   104     /// \brief Constructor to attach the new map into the registry.
   105     ///
   106     /// It constructs a map and attachs it into the registry.
   107     /// It adds all the items of the graph to the map.
   108     VectorMap(const Graph& _g) : graph(&_g) {
   109       attach(_g.getNotifier(_Item()));
   110       build();
   111     }
   112 
   113     /// \brief Constructor uses given value to initialize the map. 
   114     ///
   115     /// It constructs a map uses a given value to initialize the map. 
   116     /// It adds all the items of the graph to the map.
   117     VectorMap(const Graph& _g, const Value& _v) : graph(&_g) { 
   118       attach(_g.getNotifier(_Item()));
   119       container.resize(graph->maxId(_Item()) + 1, _v);
   120     }
   121 
   122     /// \brief Copy constructor
   123     ///
   124     /// Copy constructor.
   125     VectorMap(const VectorMap& _copy) 
   126       : Parent(), graph(_copy.getGraph()) {
   127       if (_copy.attached()) {
   128 	attach(*_copy.getRegistry());
   129 	container = _copy.container;
   130       }
   131     }
   132 
   133     /// \brief Destrcutor
   134     ///
   135     /// Destructor.
   136     virtual ~VectorMap() {
   137       if (attached()) {
   138 	detach();
   139       }
   140     }
   141 
   142 
   143   private:
   144 
   145     VectorMap& operator=(const VectorMap&);
   146 
   147   protected:
   148 
   149     using Parent::attach;
   150     using Parent::detach;
   151     using Parent::attached;
   152 
   153     const Graph* getGraph() const {
   154       return graph;
   155     }
   156 
   157   public:
   158 
   159     /// \brief The subcript operator.
   160     ///
   161     /// The subscript operator. The map can be subscripted by the
   162     /// actual items of the graph.      
   163     Reference operator[](const Key& key) {
   164       return container[graph->id(key)];
   165     } 
   166 		
   167     /// \brief The const subcript operator.
   168     ///
   169     /// The const subscript operator. The map can be subscripted by the
   170     /// actual items of the graph. 
   171     ConstReference operator[](const Key& key) const {
   172       return container[graph->id(key)];
   173     }
   174 
   175 
   176     /// \brief The setter function of the map.
   177     ///
   178     /// It the same as operator[](key) = value expression.
   179     void set(const Key& key, const Value& value) {
   180       (*this)[key] = value;
   181     }
   182 
   183   protected:
   184 
   185     /// \brief Adds a new key to the map.
   186     ///		
   187     /// It adds a new key to the map. It called by the observer registry
   188     /// and it overrides the add() member function of the observer base.     
   189     virtual void add(const Key& key) {
   190       int id = graph->id(key);
   191       if (id >= (int)container.size()) {
   192 	container.resize(id + 1);
   193       }
   194     }
   195 
   196     /// \brief Erase a key from the map.
   197     ///
   198     /// Erase a key from the map. It called by the observer registry
   199     /// and it overrides the erase() member function of the observer base.     
   200     virtual void erase(const Key&) {}
   201 
   202     /// \brief Buildes the map.
   203     ///	
   204     /// It buildes the map. It called by the observer registry
   205     /// and it overrides the build() member function of the observer base.
   206     virtual void build() { 
   207       container.resize(graph->maxId(_Item()) + 1);
   208     }
   209 
   210     /// \brief Clear the map.
   211     ///
   212     /// It erase all items from the map. It called by the observer registry
   213     /// and it overrides the clear() member function of the observer base.     
   214     virtual void clear() { 
   215       container.clear();
   216     }
   217     
   218   private:
   219 		
   220     Container container;
   221     const Graph *graph;
   222 
   223   };
   224 
   225 }
   226 
   227 #endif