I just want to make sure I wrote this circle program correctly. Please let me kn
ID: 3556073 • Letter: I
Question
I just want to make sure I wrote this circle program correctly. Please let me know if I have to make any changes.
package Chapter6;
public class Circle
{
private double radius;
private double pi=3.14159;
public Circle()
{
radius=0.0;
}
Circle(double r)
{
radius=r;
}
public void setRadius(double r)
{
radius=r;
}
public double getRadius()
{
return radius;
}
public double getArea()
{
return pi*radius*radius;
}
public double getDiameter()
{
return radius*4;
}
public double getCircumference()
{
return 2*pi*radius;
}
}
package Chapter6;
import java.util.Scanner;
public class circleTest {
public static void main(String[] args)
{
Circle object=new Circle();
double r;
Scanner keyboard = new Scanner(System.in);
System.out.println("Enter radius:");
r=keyboard.nextInt();
object.setRadius(r);
System.out.println("Area of the circle:"+object.getArea());
System.out.println("Diameter of the circle:"+object.getDiameter());
System.out.println("Circumference of the circle:"+object.getCircumference());
System.exit(0);
}
}
Explanation / Answer
public class Circle { private double radius; private double pi=3.14159; public Circle() { radius=0.0; } Circle(double r) { radius=r; } public void setRadius(double r) { radius=r; } public double getRadius() { return radius; } public double getArea() { return pi*radius*radius; } public double getDiameter() { return radius*2; // Diameter is 2*radius } public double getCircumference() { return 2*pi*radius; } } import java.util.Scanner; public class CircleTest { // Class Name should always start from Capital Letter public static void main(String[] args) { Circle object=new Circle(); double r; Scanner keyboard = new Scanner(System.in); System.out.println("Enter radius:"); r=keyboard.nextDouble(); // you should input double so that you don't lose precision object.setRadius(r); System.out.println("Area of the circle:"+object.getArea()); System.out.println("Diameter of the circle:"+object.getDiameter()); System.out.println("Circumference of the circle:"+object.getCircumference()); System.exit(0); } }