source: lemon-0.x/src/hugo/array_map_factory.h @ 804:6874a72dbdc5

// -*- c++ -*-
#ifndef ARRAY_MAP_FACTORY_H
#define ARRAY_MAP_FACTORY_H

#include <memory>

#include <hugo/extended_pair.h>

///\ingroup graphmapfactory
///\file
///\brief Graph maps that construates and destruates
///their elements dynamically.

namespace hugo {


/// \addtogroup graphmapfactory
/// @{
        
  /** The ArrayMapFactory template class is a factory class
   *  to create maps for the edge and nodes. This map factory
   *  uses the allocators to implement the container function.
   *
   *  The template parameter is the MapRegistry that the maps
   *  will belong to.
   */

  template <typename MapRegistry> 
  class ArrayMapFactory {
                
  public:
                
    /// The graph type of the maps. 
    typedef typename MapRegistry::Graph Graph;
    /// The key type of the maps.
    typedef typename MapRegistry::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename MapRegistry::KeyIt KeyIt;

    /// The MapBase of the Map which imlements the core regisitry function.
    typedef typename MapRegistry::MapBase MapBase;
                
    /** The template Map type.
     */
    template <typename V, typename A = std::allocator<V> > 
    class Map : public MapBase {
    
      public:

      /// The value type of the map.
      typedef V ValueType;

      /// The value type of the map.
      typedef V Value;
      /// The reference type of the map;
      typedef Value& Reference;
      /// The pointer type of the map;
      typedef Value* Pointer;

      /// The const value type of the map.
      typedef const Value ConstValue;
      /// The const reference type of the map;
      typedef const Value& ConstReference;
      /// The pointer type of the map;
      typedef const Value* ConstPointer;


      typedef A Allocator;

        
      /** Default constructor for the map.
       */
      Map() : values(0), capacity(0) {}
                        
      /** Graph and Registry initialized map constructor.
       */
      Map(const Graph& g, MapRegistry& r) : MapBase(g, r) {
        allocate_memory();
        for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
          int id = MapBase::getGraph()->id(it);
          allocator.construct(&(values[id]), Value());
        }                                                               
      }

      /** Constructor to use default value to initialize the map. 
       */
      Map(const Graph& g, MapRegistry& r, const Value& v) : MapBase(g, r) {
        allocate_memory();
        for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
          int id = MapBase::getGraph()->id(it);
          allocator.construct(&(values[id]), v);
        }                                                               
      }

      /** Constructor to copy a map of the same map type.
       */
      Map(const Map& copy) : MapBase(*copy.graph, *copy.registry) {
        capacity = copy.capacity;
        if (capacity == 0) return;
        values = allocator.allocate(capacity);
        for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
          int id = MapBase::getGraph()->id(it);
          allocator.construct(&(values[id]), copy.values[id]);
        }
      }

      /** Constructor to copy a map of an other map type.
       */
      template <typename CMap> Map(const CMap& copy) 
        : MapBase(copy), capacity(0), values(0) {
        if (MapBase::getGraph()) {
          allocate_memory();
          for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
            set(it, copy[it]);
          }
        }
      }

      /** Assign operator to copy a map of the same map type.
       */
      Map& operator=(const Map& copy) {
        if (&copy == this) return *this;
        if (capacity != 0) {
          MapBase::destroy();
          allocator.deallocate(values, capacity);
        }
        capacity = copy.capacity;
        if (capacity == 0) return *this;
        values = allocator.allocate(capacity);
        for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
          int id = MapBase::getGraph()->id(it);
          allocator.construct(&(values[id]), copy.values[id]);
        }
        return *this;
      }

      /** Assign operator to copy a map an other map type.
       */
      template <typename CMap> Map& operator=(const CMap& copy) {
        if (MapBase::getGraph()) {
          MapBase::destroy();
        } 
        MapBase::operator=(copy);
        if (MapBase::getGraph()) {
          allocate_memory();
          for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
            set(it, copy[it]);
          }
        }
        return *this;
      }
                                
      /** The destructor of the map.
       */
      virtual ~Map() {
        if (capacity != 0) {
          MapBase::destroy();
          allocator.deallocate(values, capacity);
        }
      }
        
        
      /**
       * The subscript operator. The map can be subscripted by the
       * actual keys of the graph. 
       */
      Value& operator[](const KeyType& key) {
        int id = MapBase::getGraph()->id(key);
        return values[id];
      } 
                
      /**
       * The const subscript operator. The map can be subscripted by the
       * actual keys of the graph. 
       */
      const Value& operator[](const KeyType& key) const {
        int id = MapBase::getGraph()->id(key);
        return values[id];
      }
        
      /** Setter function of the map. Equivalent with map[key] = val.
       *  This is a compatibility feature with the not dereferable maps.
       */
      void set(const KeyType& key, const Value& val) {
        int id = MapBase::getGraph()->id(key);
        values[id] = val;
      }
                
      /** Add a new key to the map. It called by the map registry.
       */
      void add(const KeyType& key) {
        int id = MapBase::getGraph()->id(key);
        if (id >= capacity) {
          int new_capacity = (capacity == 0 ? 1 : capacity);
          while (new_capacity <= id) {
            new_capacity <<= 1;
          }
          Value* new_values = allocator.allocate(new_capacity);;
          for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
            int jd = MapBase::getGraph()->id(it);
            if (id != jd) {
              allocator.construct(&(new_values[jd]), values[jd]);
              allocator.destroy(&(values[jd]));
            }
          }
          if (capacity != 0) allocator.deallocate(values, capacity);
          values = new_values;
          capacity = new_capacity;
        }
        allocator.construct(&(values[id]), Value());
      }
                
      /** Erase a key from the map. It called by the map registry.
       */
      void erase(const KeyType& key) {
        int id = MapBase::getGraph()->id(key);
        allocator.destroy(&(values[id]));
      }

      /** Clear the data structure.
       */
      void clear() {    
        if (capacity != 0) {
          MapBase::destroy();
          allocator.deallocate(values, capacity);
          capacity = 0;
        }
      }
        
      /** Compatible iterator with the stl maps' iterators.
       *  It iterates on pairs of a key and a value.
       */
      class iterator {
        friend class Map;
        friend class const_iterator;
      private:

        /** Private constructor to initalize the the iterators returned
         *  by the begin() and end().
         */
        iterator (Map& pmap, const KeyIt& pit) : map(&pmap), it(pit) {}

      public:

        /** Default constructor. 
         */
        iterator() {}

        typedef extended_pair<const KeyType&, const KeyType&, 
                              Value&, Value&> Reference;

        /** Dereference operator for map.
         */      
        Reference operator*() {
          return Reference(it, (*map)[it]);
        }

        class Pointer {
          friend class iterator;
        private:
          Reference data;
          Pointer(const KeyType& key, Value& val) : data(key, val) {}
        public:
          Reference* operator->() {return &data;}
        };

        /** Arrow operator for map.
         */      
        Pointer operator->() {
          return Pointer(it, ((*map)[it])); 
        }

        /** The pre increment operator of the map.
         */
        iterator& operator++() { 
          ++it; 
          return *this; 
        }

        /** The post increment operator of the map.
         */
        iterator operator++(int) { 
          iterator tmp(it); 
          ++it; 
          return tmp; 
        }

        /** The equality operator of the map.
         */
        bool operator==(const_iterator p_it) {
          return p_it.it == it;
        }
        
        /** The not-equality operator of the map.
         */
        bool operator!=(const_iterator p_it) {
          return !(*this == p_it);
        }

        
      private:
        Map* map;
        KeyIt it;
      };

      /** Returns the begin iterator of the map.
       */
      iterator begin() {
        return iterator(*this, KeyIt(*MapBase::getGraph()));
      }

      /** Returns the end iterator of the map.
       */
      iterator end() {
        return iterator(*this, INVALID);
      }

      class const_iterator {
        friend class Map;
        friend class iterator;
      private:

        /** Private constructor to initalize the the iterators returned
         *  by the begin() and end().
         */
        const_iterator (const Map& pmap, const KeyIt& pit) 
          : map(&pmap), it(pit) {}

      public:

        /** Default constructor. 
         */
        const_iterator() {}

        /** Constructor to convert iterator to const_iterator.
         */
        const_iterator(iterator p_it) : map(p_it.map), it(p_it.it) {}
      
        typedef extended_pair<const KeyType&, const KeyType&, 
          const Value&, const Value&> Reference;

        /** Dereference operator for map.
         */      
        Reference operator*() {
          return Reference(it, (*map)[it]);
        }


        class Pointer {
          friend class const_iterator;
        private:
          Reference data;
          Pointer(const KeyType& key, const Value& val) : data(key, val) {}
        public:
          Reference* operator->() {return &data;}
        };

        /** Arrow operator for map.
         */      
        Pointer operator->() {
          return Pointer(it, ((*map)[it])); 
        }

        /** The pre increment operator of the map.
         */
        const_iterator& operator++() { 
          ++it; 
          return *this; 
        }

        /** The post increment operator of the map.
         */
        const_iterator operator++(int) { 
          const_iterator tmp(it); 
          ++it; 
          return tmp; 
        }

        /** The equality operator of the map.
         */
        bool operator==(const_iterator p_it) {
          return p_it.it == it;
        }
        
        /** The not-equality operator of the map.
         */
        bool operator!=(const_iterator p_it) {
          return !(*this == p_it);
        }
        

      private:
        const Map* map;
        KeyIt it;
      };

      /** Returns the begin const_iterator of the map.
       */
      const_iterator begin() const {
        return const_iterator(*this, KeyIt(*MapBase::getGraph()));
      }

      /** Returns the end const_iterator of the map.
       */
      const_iterator end() const {
        return const_iterator(*this, INVALID);
      }

    private:
      
      void allocate_memory() {
        int max_id = -1;
        for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {
          int id = MapBase::getGraph()->id(it);
          if (id > max_id) {
            max_id = id;
          }                     
        }
        if (max_id == -1) {
          capacity = 0;
          values = 0;
          return;
        }
        capacity = 1;
        while (capacity <= max_id) {
          capacity <<= 1;
        }
        values = allocator.allocate(capacity);  
      }      

      int capacity;
      Value* values;
      Allocator allocator;
    };          
  };

/// @}

}

#endif