circle.java

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/*
 * Circle - a Shape representing a circle
 */
import java.lang.Math;        // for PI

public class Circle extends Shape
{
    // Attributes
    private double radius;

    // Constructors
    public Circle()
    {
        super();
        radius = 0.0;
    }
    
    public Circle(final Point org, final double rad)
    {
        super(org);
        radius = rad;
    }

    // Methods
    public double area()
    {
        return Math.PI * radius * radius;  // Pi r Squared
    }

    public double getRadius()
    {
        return radius;
    }

    public double perimeter()
    {
        return 2 * Math.PI * radius;    // 2 PI r
    }

    public void setRadius(double r)
    {
        radius = r;
    }
}