circle.java

来自「Java程序设计技巧与开发实例附书源代码。」· Java 代码 · 共 26 行

public class Circle
    extends Shape
{
   protected double radius;
   public Circle(double _radius)
   {
      type = "Circle";
      radius = _radius;
   }

   public void computeArea()
   {
      area = Math.PI * radius * radius;
   }

   public void computePerimeter()
   {
      perim = 2.0 * Math.PI * radius;
   }

   public String toString()
   {
      return super.toString() + "\n\tRadius = " + radius;
   }
}