//  Example program from the text
//   
//  A multilevel hierarchy. 
//
class TwoDShape { 
  private double width; 
  private double height; 
 
  // A default constructor. 
  TwoDShape() { 
    width = height = 0.0; 
  } 
 
  // Parameterized constructor. 
  TwoDShape(double w, double h) { 
    width = w; 
    height = h; 
  } 
 
  // Construct object with equal width and height. 
  TwoDShape(double x) { 
    width = height = x; 
  } 
 
  // Accessor methods for width and height. 
  double getWidth() { return width; } 
  double getHeight() { return height; } 
  void setWidth(double w) { width = w; } 
  void setHeight(double h) { height = h; } 
 
  void showDim() { 
    System.out.println("Width and height are " + 
                       width + " and " + height); 
  } 
} 
 
// Extend TwoDShape. 
class Triangle extends TwoDShape { 
  private String style; 
   
  // A default constructor. 
  Triangle() { 
    super(); 
    style = "none"; 
  } 
 
  Triangle(String s, double w, double h) { 
    super(w, h); // call superclass constructor 
 
    style = s;  
  } 
 
  // One argument constructor. 
  Triangle(double x) { 
    super(x); // call superclass constructor 
 
    style = "filled";  
  } 
 
  double area() { 
    return getWidth() * getHeight() / 2; 
  } 
 
  void showStyle() { 
    System.out.println("Triangle is " + style); 
  } 
} 
 
// Extend Triangle. 
class ColorTriangle extends Triangle { 
  private String color; 
 
  ColorTriangle(String c, String s, 
                double w, double h) { 
    super(s, w, h); 
 
    color = c; 
  } 
 
  String getColor() { return color; } 
 
  void showColor() { 
    System.out.println("Color is " + color); 
  } 
} 
 
class Shapes6 { 
  public static void main(String args[]) { 
    ColorTriangle t1 =  
         new ColorTriangle("Blue", "outlined", 8.0, 12.0); 
    ColorTriangle t2 =  
         new ColorTriangle("Red", "filled", 4.0, 2.0); 
 
    System.out.println("Info for t1: "); 
    t1.showStyle(); 
    t1.showDim(); 
    t1.showColor(); 
    System.out.println("Area is " + t1.area()); 
 
    System.out.println(); 
 
    System.out.println("Info for t2: "); 
    t2.showStyle(); 
    t2.showDim(); 
    t2.showColor(); 
    System.out.println("Area is " + t2.area()); 
  } 
}