《21天学通C++》第三周复习清单 - c++编程基础

// *******************************************************************

// Title:Week 3 in Review

// File:Week3

// Description:Provide a template-based linked list

//demonstration program with exception handling

// Classes:PART - holds part numbers and potentially other

//information about parts, This will be the

//example class for the list to hold

//Note use of operator<< to print the

//information about a part based on its

//runtime type.

//Node - acts as a node in a list

//List - template-based list which provides the

//mechanisms for a linked list

// Author:Jesse Liberty (jl)

// Developed:Pentium 200 Pro. 128MB RAM MVC 5.0

// Target:Platform independent

// Rev History:9/94 - First release (jl)

//4/97 - Updated (jl)

// *******************************************************************

#include

using namespace std;

// exception classes

class Exception {};

class OutOfMemory :public Exception{};

class NullNode :public Exception{};

class EmptyList :public Exception{};

class BoundsError :public Exception{};

// **************** Part ************

// Abstract base class of parts

class Part

{

public:

Part():itsObjectNumber(1) {}

Part(int ObjectNumber):itsObjectNumber(ObjectNumber){}

virtual ~Part(){};

int GetObjectNumber() const { return itsObjectNumber; }

virtual void Display() const =0;// must be overridden

private:

int itsObjectNumber;

};

// implementation of pure virtual function so that

// derived classes can chain up

void Part::Display() const

{

cout << " Part Number: " << itsObjectNumber << endl;

}

// this one operator<< will be called for all part objects.

// It need not be a friend as it does not access private data

// It calls Display() which uses the required polymorphism

// Wed like to be able to override this based on the real type

// of thePart, but C++ does not support contravariance

ostream& operator<<( ostream& theStream,Part& thePart)

{

thePart.Display();// virtual contravariance!

return theStream;

}

// **************** Car Part ************

class CarPart : public Part

{

public:

CarPart():itsModelYear(94){}

CarPart(int year, int partNumber);

int GetModelYear() const { return itsModelYear; }

virtual void Display() const;

private:

int itsModelYear;

};

CarPart::CarPart(int year, int partNumber):

itsModelYear(year),

Part(partNumber)

{}

void CarPart::Display() const

{

Part::Display();

cout << "Model Year: " << itsModelYear << endl;

}

// **************** AirPlane Part ************

class AirPlanePart : public Part

{

public:

AirPlanePart():itsEngineNumber(1){};

AirPlanePart(int EngineNumber, int PartNumber);

virtual void Display() const;

int GetEngineNumber() const { return itsEngineNumber; }

private:

int itsEngineNumber;

};

AirPlanePart::AirPlanePart(int EngineNumber, int PartNumber):

itsEngineNumber(EngineNumber),

Part(PartNumber)

{}

void AirPlanePart::Display() const

{

Part::Display();

cout << "Engine No.: " << itsEngineNumber << endl;

}

// forward declaration of class List

template

class List;

// **************** Node **************

// Generic node, can be added to a list

// ************************************

template

class Node

{

public:

friend class List;

Node (T*);

~Node();

void SetNext(Node * node) { itsNext = node; }

Node * GetNext() const;

T * GetObject() const;

private:

T* itsObject;

Node * itsNext;

};

// Node Implementations...

template

Node::Node(T* pObject):

itsObject(pObject),

itsNext(0)

{}

template

Node::~Node()

{

delete itsObject;

itsObject = 0;

delete itsNext;

《21天学通C++》第三周复习清单(一)