testclassobj.java

java的小程序

public class TestClassObj
{
   public static void main(String args[])
   {
      Circle c1=new Circle();
      Class metaCircle=c1.getClass();
      System.out.println("Object c1's Name is "+metaCircle.getName());
   }
}
class Circle
{   
     protected double radius;
     public Circle()
     {
        this(1.0);
     }
     public Circle(double r)
     {
        this.radius = r;
     }
     public double getRadius()
     {
        return radius;
     }
     public void setRadius(double radius)
     {
        this.radius = radius;
     }
     public double findArea()
     {
        return radius*radius*Math.PI;
     }
     public double findPerimeter()
     {
         return 2*radius*Math.PI;
     }
}