c08p409b.txt

Data Abstraction & Problem Solving with C++源码

// *********************************************************
// Header file List.h for the ADT list.
// Uses ListNode and BasicADT.
// *********************************************************
#include "ListNode.h"   // as specified in previous section,
                        // also specifies ListItemType
#include "ListException.h" 
#include "ListIndexOutOfRangeException.h"
#include "BasicADT.h"

class List : public BasicADT
{
public:
// constructors and destructor:
   List();
   List(const List& aList);
   virtual ~List();

// list operations:
   virtual bool isEmpty() const;
   virtual int getLength() const;
   virtual void insert(int index, ListItemType newItem) 
         throw(ListIndexOutOfRangeException, ListException);
   virtual void remove(int index) 
         throw(ListIndexOutOfRangeException);
   virtual void retrieve(int index, 
                   ListItemType& dataItem) const 
         throw(ListIndexOutOfRangeException);

protected:
   void setSize(int newSize);       // sets size
   ListNode *getHead() const;       // returns head pointer
   void setHead(ListNode *newHead); // sets head pointer

   // the next two functions return the list item or 
   // next pointer of a node in the linked list
   ListItemType getNodeItem(ListNode *ptr) const;
   ListNode *getNextNode(ListNode *ptr) const;

private:
   int      size;    // number of items in the list
   ListNode *head;   // pointer to the linked list

   ListNode *find(int index) const;
};  // end class