Defining Classes II - Absolute Java - page 276

Display 5.7 Using Math.PI

1 import java.util.Scanner;

2 /**
3 Class with static methods for circles and spheres.
4 */
5 public class RoundStuff3
6 {

7 /**
8 Return the area of a circle of the given radius.
9 */
10 public static double area( double radius)
11 {
12 return (Math.PI*radius*radius);
13 }
14
15 /**
16 Return the volume of a sphere of the given radius.
17 */
18 public static double volume(double radius)
19 {
20 return ((4.0/3.0)*Math.PI*radius*radius*radius);
21 }

22 public static void main(String[] args)
23 {
24 Scanner keyboard = new Scanner(System.in);
25 System.out.println("Enter radius:");
26 double radius = keyboard.nextDouble();
27
28 System.out.println("A circle of radius"
29 + radius + "inches");
30 System.out.println("has an area of" +
31 RoundStuff.area(radius) + "square inches.");
32 System.out.println("A sphere of radius"
33 + radius + "inches");
34 System.out.println("has a volume of " +
35 RoundStuff.volume(radius) + "cubic inches.");
36 }
37 }
38
39

The dialogue is the same as in
Display 5.1.