Shape.h

1
Shape.h

• // SHAPE.H
• // Definition of abstract base class Shape
• ifndef SHAPE_H
• define SHAPE_H
• class Shape
• public
• virtual float area() const return 0.0
• virtual float volume() const return 0.0
• virtual void printShapeName() const 0 //
  pure virtual
• virtual void print() const 0 //
  pure virtual
• endif

Shape
Point
Circle
Cylinder
2
Topics

• Inheritance
• Syntax.
• What does it mean to inherit.
• Types (public, private, protected).
• Overriding member functions (virtual keyword).
• Operator overloading.
• Friend functions.
• Constructors can call parent constructors.
• Destructors are called in order of child to
  parent.

3
Point1.h

• // POINT1.H
• // Definition of class Point
• ifndef POINT1_H
• define POINT1_H
• include ltiostream.hgt
• include "shape.h"
• class Point public Shape
• friend ostream operatorltlt(ostream , const
  Point )
• public
• Point(float 0, float 0) // default
  constructor
• void setPoint(float, float)
• float getX() const return x
• float getY() const return y
• virtual void printShapeName() const cout ltlt
  "Point "
• virtual void print() const
• private
• float x, y // x and y coordinates of Point

4
Point1.cpp

• // POINT1.CPP
• // Member function definitions for class Point
• include ltiostream.hgt
• include "point1.h"
• PointPoint(float a, float b)
• setPoint(a, b)
• void PointsetPoint(float a, float b)
• x a
• y b
• void Pointprint() const cout ltlt '' ltlt x ltlt
  ", " ltlt y ltlt ''
• ostream operatorltlt(ostream output, const Point
  p)
• p.print() // call print to output the
  object

5
Circle.h

• // CIRCLE1.H
• // Definition of class Circle
• ifndef CIRCLE1_H
• define CIRCLE1_H
• include "point1.h"
• class Circle public Point
• friend ostream operatorltlt(ostream , const
  Circle )
• public
• // default constructor
• Circle(float r 0.0, float x 0.0, float y
  0.0)
• void setRadius(float)
• float getRadius() const
• virtual float area() const
• virtual void printShapeName() const cout ltlt
  "Circle "
• virtual void print() const
• private
• float radius // radius of Circle

6
Circle.cpp

• // CIRCLE1.CPP
• // Member function definitions for class Circle
• include ltiostream.hgt
• include ltiomanip.hgt
• include "circle1.h"
• CircleCircle(float r, float a, float b)
• Point(a, b) // call base-class constructor
• radius r gt 0 ? r 0
• void CirclesetRadius(float r) radius r gt 0
  ? r 0
• float CirclegetRadius() const return radius
  
• float Circlearea() const return 3.14159
  radius radius
• void Circleprint() const
• cout ltlt '' ltlt getX() ltlt ", " ltlt getY()
• ltlt " Radius" ltlt setiosflags(iosshowpo
  int)

7
Cylindr1.h

• // CYLINDR1.H
• // Definition of class Cylinder
• ifndef CYLINDR1_H
• define CYLINDR1_H
• include "circle1.h"
• class Cylinder public Circle
• friend ostream operatorltlt(ostream , const
  Cylinder )
• public
• // default constructor
• Cylinder(float h 0.0, float r 0.0,
• float x 0.0, float y 0.0)
• void setHeight(float)
• virtual float area() const
• virtual float volume() const
• virtual void printShapeName() const cout ltlt
  "Cylinder "
• virtual void print() const
• private

8
Cylindr1.cpp

• include ltiostream.hgt
• include ltiomanip.hgt
• include "cylindr1.h"
• CylinderCylinder(float h, float r, float x,
  float y)
• Circle(r, x, y) // call base-class
  constructor
• height h gt 0 ? h 0
• void CylindersetHeight(float h) height h gt
  0 ? h 0
• float Cylinderarea() const // surface area of
  Cylinder
• return 2 Circlearea()
• 2 3.14159 CirclegetRadius()
  height
• float Cylindervolume() const return
  Circlearea() height
• void Cylinderprint() const
• cout ltlt '' ltlt getX() ltlt ", " ltlt getY()
• ltlt " Radius" ltlt setiosflags(iosshowpo
  int)

9
Main

• main()
• Point point(7, 11) // create
  a Point
• Circle circle(3.5, 22, 8) // create
  a Circle
• Cylinder cylinder(10, 3.3, 10, 10) // create
  a Cylinder
• point.printShapeName() // static binding
• cout ltlt point ltlt endl
• circle.printShapeName() // static binding
• cout ltlt circle ltlt endl
• cylinder.printShapeName() // static binding
• cout ltlt cylinder ltlt "\n\n"
• cout ltlt setiosflags(iosshowpoint) ltlt
  setprecision(2)
• Shape arrayOfShapes3 // array of
  base-class pointers
• arrayOfShapes0 point
• arrayOfShapes1 circle
• arrayOfShapes2 cylinder
• for (int i 0 i lt 3 i)