Monthly Archives: December 2013

Circle Class

Create the following class

Circle

download-bttnCircle
Constructor 

  • public Circle( double _radius, int _col)

instance Variables

  • double radius
  • int color

Accesor Methods

  • public double getArea(); //returns the area of the triangle
  • public double getCircum() ;// returns the circumference

What should Circle Extend?

circle_should_extend_what

Answer!

Constructors And Inheritance

What relationships exist between super and sub classes?

 

  • How can we use superclasses to improve ourInteractiveMath2 code?
    • To be implemented in  computeNetArea() method
    • How can an element in the Polygon2 ‘ list that  is a RightTriangle2 call the getHypotenuse() method?
      • To be implemented in the new method void printDetails() which should , among other , things print the hypotenuse length for any RightTriangle2’s?
  • What is Inherited by subclasses?
    • Constructors?
    • instance variables
    • static variables?

 Next: What if we want to add a Circle Class

SuperClasses are Great II

How can we improve our current class structure?right_triangle_rectangle

 

 

 

 

 

 

 

We are going to create a second “Generation” of classes and will denote this change by appending a ‘2’ to the names of all classes in this “generation”

right_triangle_extends_polygon

 

Class: Polygon2 (superclass of Triangle2, Rectangle2)  Polygon2download-bttn

 

Constructor 

public Polygon2(int _col, double _width, double _height, int _sides)

instance Variables

  • private int color;
  • private int numSides
  • protected double width;
  • protected double height

Methods

  • public int getColor()
  • public double getWidth()
  • public double getHeight()

Class: Rectangle2 extends Polygon2  Rectangle2download-bttn

instance Variables

None needed (see superclass)

Accesor Methods //override each of the superclass

  • public double getArea(); //returns the area of the triangle

Class: RightTriangle2 extends Polygon2  RightTriangle2download-bttn

instance Variables

None needed (see superclass)

Accesor Methods //override each of the superclass

  • public double getArea(); //returns the area of the triangle
  • public double getHypotenuse()

InteractiveMath2   InteractiveMath2download-bttn

 

Next: What is inherited?

Super Classes Are Great I

 

Question: What limitations seem to exist with our use of classes?

 

I. Implement all Methods of the Triangle and Rectangle methods below

right_triangle_rectangle

 

Class: Rectangle  download-bttnRectangle

Constructor 

  • public Rectangle ( int  _col,  double  _width,  double _height)

instance Variables

  • private int color;
  • private double width;
  • private double height ;

Accessor Methods

  • public double getArea(); //returns the area of the rectangle
  • public int getColor()

 

Class: RightTriangle  download-bttnRightTriangle

Constructor 

  • public RightTriangle( int _col,  double  _width,  double _height)

instance Variables

  • private int color;
  • private double width;
  • private double height;

Accessor Methods

  • public double getArea(); //returns the area of the triangle
  • public int getColor()
  • public double getHypotenuse() ;

Class: InteractiveMath

download-bttn InteractiveMath-Arraylists (USE THIS ONE)

instance Variables

  • ArrayList<Rectangle> rectangles;
  • ArrayList<RightTriangle> triangles;

Accesor Methods

  • public double computeNetArea(){ //@ returns the area of the rectangles and triangles

 

Next  : Super Classes are great 2

Then  : constructors and inheritance.

after that : What is “Inherited” by Subclasses?

 

 

interactiveMath_arrays