1: /** 2: A class of circles. 3: */ 4: public class Circle implements Measurable 5: { 6: private double myRadius; 7: public Circle(double radius) 8: { 9: myRadius = radius; 10: } 11: public double getPerimeter() 12: { 13: return 2 * Math.PI * myRadius; 14: } 15: public double getCircumference() 16: { 17: return getPerimeter(); 18: } 19: public double getArea() 20: { 21: return Math.PI * myRadius * myRadius; 22: } 23: }