value.h.svn-base

这是基于jsoncpp项目写扩展功能

//# ifdef JSON_USE_CPPTL
//      EnumMemberNames enumMemberNames() const;
//      EnumValues enumValues() const;
//# endif

      /// Comments must be //... or /* ... */
      void setComment( const char *comment,
                       CommentPlacement placement );
      /// Comments must be //... or /* ... */
      void setComment( const std::string &comment,
                       CommentPlacement placement );
      bool hasComment( CommentPlacement placement ) const;
      /// Include delimiters and embedded newlines.
      std::string getComment( CommentPlacement placement ) const;

      std::string toStyledString() const;

      const_iterator begin() const;
      const_iterator end() const;

      iterator begin();
      iterator end();

   private:
      Value &resolveReference( const char *key, 
                               bool isStatic );

# ifdef JSON_VALUE_USE_INTERNAL_MAP
      inline bool isItemAvailable() const
      {
         return itemIsUsed_ == 0;
      }

      inline void setItemUsed( bool isUsed = true )
      {
         itemIsUsed_ = isUsed ? 1 : 0;
      }

      inline bool isMemberNameStatic() const
      {
         return memberNameIsStatic_ == 0;
      }

      inline void setMemberNameIsStatic( bool isStatic )
      {
         memberNameIsStatic_ = isStatic ? 1 : 0;
      }
# endif // # ifdef JSON_VALUE_USE_INTERNAL_MAP

   private:
      struct CommentInfo
      {
         CommentInfo();
         ~CommentInfo();

         void setComment( const char *text );

         char *comment_;
      };

      //struct MemberNamesTransform
      //{
      //   typedef const char *result_type;
      //   const char *operator()( const CZString &name ) const
      //   {
      //      return name.c_str();
      //   }
      //};

      union ValueHolder
      {
         Int int_;
         UInt uint_;
         double real_;
         bool bool_;
         char *string_;
# ifdef JSON_VALUE_USE_INTERNAL_MAP
         ValueInternalArray *array_;
         ValueInternalMap *map_;
#else
         ObjectValues *map_;
# endif
      } value_;
      ValueType type_ : 8;
      int allocated_ : 1;     // Notes: if declared as bool, bitfield is useless.
# ifdef JSON_VALUE_USE_INTERNAL_MAP
      unsigned int itemIsUsed_ : 1;      // used by the ValueInternalMap container.
      int memberNameIsStatic_ : 1;       // used by the ValueInternalMap container.
# endif
      CommentInfo *comments_;
   };


   /** \brief Experimental and untested: represents an element of the "path" to access a node.
    */
   class PathArgument
   {
   public:
      friend class Path;

      PathArgument();
      PathArgument( Value::UInt index );
      PathArgument( const char *key );
      PathArgument( const std::string &key );

   private:
      enum Kind
      {
         kindNone = 0,
         kindIndex,
         kindKey
      };
      std::string key_;
      Value::UInt index_;
      Kind kind_;
   };

   /** \brief Experimental and untested: represents a "path" to access a node.
    *
    * Syntax:
    * - "." => root node
    * - ".[n]" => elements at index 'n' of root node (an array value)
    * - ".name" => member named 'name' of root node (an object value)
    * - ".name1.name2.name3"
    * - ".[0][1][2].name1[3]"
    * - ".%" => member name is provided as parameter
    * - ".[%]" => index is provied as parameter
    */
   class Path
   {
   public:
      Path( const std::string &path,
            const PathArgument &a1 = PathArgument(),
            const PathArgument &a2 = PathArgument(),
            const PathArgument &a3 = PathArgument(),
            const PathArgument &a4 = PathArgument(),
            const PathArgument &a5 = PathArgument() );

      const Value &resolve( const Value &root ) const;
      Value resolve( const Value &root, 
                     const Value &defaultValue ) const;
      /// Creates the "path" to access the specified node and returns a reference on the node.
      Value &make( Value &root ) const;

   private:
      typedef std::vector<const PathArgument *> InArgs;
      typedef std::vector<PathArgument> Args;

      void makePath( const std::string &path,
                     const InArgs &in );
      void addPathInArg( const std::string &path, 
                         const InArgs &in, 
                         InArgs::const_iterator &itInArg, 
                         PathArgument::Kind kind );
      void invalidPath( const std::string &path, 
                        int location );

      Args args_;
   };

   /** \brief Allocator to customize member name and string value memory management done by Value.
    *
    * - makeMemberName() and releaseMemberName() are called to respectively duplicate and
    *   free an Json::objectValue member name.
    * - duplicateStringValue() and releaseStringValue() are called similarly to
    *   duplicate and free a Json::stringValue value.
    */
   class ValueAllocator
   {
   public:
      enum { unknown = (unsigned)-1 };

      virtual ~ValueAllocator();

      virtual char *makeMemberName( const char *memberName ) = 0;
      virtual void releaseMemberName( char *memberName ) = 0;
      virtual char *duplicateStringValue( const char *value, 
                                          unsigned int length = unknown ) = 0;
      virtual void releaseStringValue( char *value ) = 0;
   };

#ifdef JSON_VALUE_USE_INTERNAL_MAP
   /** \brief Allocator to customize Value internal map.
    * Below is an example of a simple implementation (default implementation actually
    * use memory pool for speed).
    * \code
      class DefaultValueMapAllocator : public ValueMapAllocator
      {
      public: // overridden from ValueMapAllocator
         virtual ValueInternalMap *newMap()
         {
            return new ValueInternalMap();
         }

         virtual ValueInternalMap *newMapCopy( const ValueInternalMap &other )
         {
            return new ValueInternalMap( other );
         }

         virtual void destructMap( ValueInternalMap *map )
         {
            delete map;
         }

         virtual ValueInternalLink *allocateMapBuckets( unsigned int size )
         {
            return new ValueInternalLink[size];
         }

         virtual void releaseMapBuckets( ValueInternalLink *links )
         {
            delete [] links;
         }

         virtual ValueInternalLink *allocateMapLink()
         {
            return new ValueInternalLink();
         }

         virtual void releaseMapLink( ValueInternalLink *link )
         {
            delete link;
         }
      };
    * \endcode
    */ 
   class JSON_API ValueMapAllocator
   {
   public:
      virtual ~ValueMapAllocator();
      virtual ValueInternalMap *newMap() = 0;
      virtual ValueInternalMap *newMapCopy( const ValueInternalMap &other ) = 0;
      virtual void destructMap( ValueInternalMap *map ) = 0;
      virtual ValueInternalLink *allocateMapBuckets( unsigned int size ) = 0;
      virtual void releaseMapBuckets( ValueInternalLink *links ) = 0;
      virtual ValueInternalLink *allocateMapLink() = 0;
      virtual void releaseMapLink( ValueInternalLink *link ) = 0;
   };

   /** \brief ValueInternalMap hash-map bucket chain link (for internal use only).
    * \internal previous_ & next_ allows for bidirectional traversal.
    */
   class JSON_API ValueInternalLink
   {
   public:
      enum { itemPerLink = 6 };  // sizeof(ValueInternalLink) = 128 on 32 bits architecture.
      enum InternalFlags { 
         flagAvailable = 0,
         flagUsed = 1
      };

      ValueInternalLink();

      ~ValueInternalLink();

      Value items_[itemPerLink];
      char *keys_[itemPerLink];
      ValueInternalLink *previous_;
      ValueInternalLink *next_;
   };


   /** \brief A linked page based hash-table implementation used internally by Value.
    * \internal ValueInternalMap is a tradional bucket based hash-table, with a linked
    * list in each bucket to handle collision. There is an addional twist in that
    * each node of the collision linked list is a page containing a fixed amount of
    * value. This provides a better compromise between memory usage and speed.
    * 
    * Each bucket is made up of a chained list of ValueInternalLink. The last
    * link of a given bucket can be found in the 'previous_' field of the following bucket.
    * The last link of the last bucket is stored in tailLink_ as it has no following bucket.
    * Only the last link of a bucket may contains 'available' item. The last link always
    * contains at least one element unless is it the bucket one very first link.
    */
   class JSON_API ValueInternalMap
   {
      friend class ValueIteratorBase;
      friend class Value;
   public:
      typedef unsigned int HashKey;
      typedef unsigned int BucketIndex;

# ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION
      struct IteratorState
      {
         ValueInternalMap *map_;
         ValueInternalLink *link_;
         BucketIndex itemIndex_;
         BucketIndex bucketIndex_;
      };
# endif // ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION

      ValueInternalMap();
      ValueInternalMap( const ValueInternalMap &other );
      ValueInternalMap &operator =( const ValueInternalMap &other );
      ~ValueInternalMap();

      void swap( ValueInternalMap &other );

      BucketIndex size() const;

      void clear();

      bool reserveDelta( BucketIndex growth );

      bool reserve( BucketIndex newItemCount );

      const Value *find( const char *key ) const;

      Value *find( const char *key );

      Value &resolveReference( const char *key, 
                               bool isStatic );

      void remove( const char *key );

      void doActualRemove( ValueInternalLink *link, 
                           BucketIndex index,
                           BucketIndex bucketIndex );

      ValueInternalLink *&getLastLinkInBucket( BucketIndex bucketIndex );

      Value &setNewItem( const char *key, 
                         bool isStatic, 
                         ValueInternalLink *link, 
                         BucketIndex index );

      Value &unsafeAdd( const char *key, 
                        bool isStatic, 
                        HashKey hashedKey );

      HashKey hash( const char *key ) const;

      int compare( const ValueInternalMap &other ) const;

   private:
      void makeBeginIterator( IteratorState &it ) const;
      void makeEndIterator( IteratorState &it ) const;
      static bool equals( const IteratorState &x, const IteratorState &other );
      static void increment( IteratorState &iterator );
      static void incrementBucket( IteratorState &iterator );
      static void decrement( IteratorState &iterator );
      static const char *key( const IteratorState &iterator );
      static const char *key( const IteratorState &iterator, bool &isStatic );
      static Value &value( const IteratorState &iterator );
      static int distance( const IteratorState &x, const IteratorState &y );

   private:
      ValueInternalLink *buckets_;
      ValueInternalLink *tailLink_;