Question

Java code for the following inheritance hierarchy figure..

1. Create class Point, with two private instance variables x and y that represented for the coordinates for a point.

Provide constructor for initialising two instance variables.

Provide set and get methods for each instance variable,

Provide toString method to return formatted string for a point coordinates.

2. Create class Circle, its inheritance from Point.

Provide a integer private radius instance variable.

Provide constructor to initialise the center coordinates and radius for a circle,.In the constructor it must call its superclass constructor by using super(x,y);

Provide set and get for the radius instance variable.

Provide two methods for calculating its area and perimeter.

Provide a toString method to return a formatted string for circle features. In the process, it must call its superclass toString method by using super.toString().

3. Similar to the above class Circle definition, Design Rectangle class.

4. Similar to the above class Rectangle definition, Design Cube class,

It has a hight instance variable.

Calculate the surface area and volume for a Cube.

5. Design a test-class to test the above four classes functionality

It creates four objects for these classes and calls the corresponding methods to test complete functionality for each class.

y for each class for each class. Point Rectangle Circle Cube Figure: Shape inheritance hierarchy

Answer 1

class Point
{
private int x;
private int y;
public Point()
{
this.x = 0;
this.y = 0;
}
public Point(int x,int y)// constructor
{
this.x = x;
this.y = y;
}
// set and get methods
public int getX()
{
return this.x;
}
public int getY()
{
return this.y;
}
public void setX(int x)
{
this.x = x;
}
public void setY(int y)
{
this.y = y;
}
public String toString()
{
return "Point("+getX() +","+getY()+")";
}
};
class Circle extends Point
{
  
private int radius;

public Circle()
{
super(0,0);
radius = 0;
  
}
public Circle(int x,int y,int radius)// constructor
{
super(x,y);
this.radius = radius ;
}

// set and get methods
public int getRadius()
{
return radius;
}
  
  
public double getArea() //compute the area of the circle
{
double area;
area = 3.14*radius*radius;
return area;
}
public double getPerimeter() //compute the perimeter of circle
{
return 2*3.14*radius;
}
public String toString()
{
return "Circle : Center :"+ getX() +","+ getY() +" radius :"+getRadius() ;
}
}
  
  
class Rectangle extends Point
{

private int length,width;

public Rectangle()
{
super(0,0);
length = 0;
width = 0;
}
public Rectangle(int x,int y,int length,int width)
{
super(x,y);
this.length = length;
this.width = width;
}
public int getLength()
{
return length;
}
public int getWidth()
{
   return width;
}
  
public void setLength(int length)
{
this.length = length;
}
public double getArea() //compute the area of the square.
{
double area;
area = length * width;
return area;
}

public String toString()
{
return "Rectangle : Top left Point :"+ getX() +","+ getY() +" length :"+getLength() +" width : "+getWidth();
}
}
  
class Cube extends Point
   {
private Point p;
private int depth;

public Cube()
{
super(0,0);
depth = 0;
  
}
public Cube(int x,int y,int depth)// constructor
{
super(x,y);
this.depth = depth;
}

// set and get methods
public int getDepth()
{
return depth;
}
  
public Point getPoint()
{
return this.p;
}
public double getArea() //compute the area of the cube
{
double area;
area = 6*getDepth()*getDepth();
return area;
}
public double getVolume() //compute the volume of the cube
{
double vol;
vol = getDepth() * getDepth() * getDepth();
return vol;
}
public String toString()
{
return "Cube : Top left Point :"+ getX() +","+ getY() +" depth :"+getDepth() ;
}
}

class GeometricTest
{
public static void main (String[] args)
{
  
  
Circle circle = new Circle(3,-1,6);
System.out.println(circle.toString());
System.out.println("Area of Circle = "+circle.getArea());
  

Rectangle r = new Rectangle(1,2,4,5);
System.out.println(r.toString());
System.out.println("Area of Rectangle = "+r.getArea());

  
Cube c = new Cube(4,5,2);

System.out.println(c.toString());
System.out.println("Area of cube = "+c.getArea());
System.out.println("Volume of cube = "+c.getVolume());

  
  
}

}

Output:

Success #stdin #stdout 0.05s 2184192KB

Circle : Center :3,-1 radius :6
Area of Circle = 113.03999999999999
Rectangle : Top left Point :1,2 length :4 width : 5
Area of Rectangle = 20.0
Cube : Top left Point :4,5  depth :2
Area of cube = 24.0
Volume of cube = 8.0

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