清华大学：JAVA教学课件：5-9

程序5-10
public class Circle {
static double PI = 3.14159265;
int radius;
public double circumference() {
return 2 * PI * radius;
}
}
public class CircumferenceTester {
public static void main(String args[]) {
Circle c1 = new Circle();
c1.radius = 50;
Circle c2 = new Circle();
c2.radius = 10;
double circum1 = c1.circumference();
double circum2 = c2.circumference();
System.out.println("Circle 1 has circumference " + circum1);
System.out.println("Circle 2 has circumference " + circum2);
}
}