Question

*JAVA*

Assume that there already exists a class called ThreeDimensionalShape. Assume that this class has many subclasses, one of them being Cylinder. Assume that ThreeDimensionalShape has an instance method called getVolume() that returns the volume of the object (a double) and that this method is overridden in all of the subclasses. (You do not need to write any of these classes.)

Write a method with this header: public static double volumeOfCylinders( ThreeDimensionalShapes[] shapes)

It should return a value representing the volume of all the Cylinders in the array

Answer 1

abstract class ThreeDimensionalShapes
{

public abstract double getVolume();
};

class Cylinder extends ThreeDimensionalShapes
{
private double radius;
private double height;
public Cylinder(double radius,double height)
{
this.radius = radius;
this.height = height;
}

public double getVolume()
{
return 3.14*radius*radius*height;
}
}

class Test
{
   public static void main (String[] args)
   {
  
   ThreeDimensionalShapes[] shapes = new Cylinder[3];
   shapes[0] = new Cylinder(4.3,6.6);
   shapes[1] = new Cylinder(3.3,4.6);
   shapes[2] = new Cylinder(2.3,2.6);
  
   System.out.printf("Volume of all cylinders : %.2f",volumeOfCylinders(shapes));
  
   }
   public static double volumeOfCylinders( ThreeDimensionalShapes[] shapes)
   {
       double totalVolume = 0.0;
       for(int i=0;i<shapes.length;i++)
       {
           System.out.println("Volume of cylinder "+(i+1)+" : "+shapes[i].getVolume());
           totalVolume += shapes[i].getVolume();
       }
       return totalVolume;
   }
}

Output:

Volume of cylinder 1 : 383.18676 Volume of cylinder 2 : 157.29515999999998 Volume of cylinder 3 : 43.18756 Volume of all cylinders : 583.67

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