Designing Classes - Java Concepts - page 526

ȗ public static double cylinderVolume(double r,
double h)

ȗ public static double cylinderSurface(double
r, double h)

ȗ public static double coneVolume(double r,
double h)

ȗ public static double coneSurface(double r,
double h)

that compute the volume and surface area of a sphere with radius r , a
cylinder with circular base with radius r and height h , and a cone with
circular base with radius r and height h . Place them into a class
Geometry . Then write a program that prompts the user for the values of
r and h , calls the six methods, and prints the results.

΢΢ Exercise P8.6. Solve Exercise P8.5 by implementing classes Sphere ,
Cylinder , and Cone . Which approach is more object-oriented?

΢΢ Exercise P8.7. Write methods

public static double
perimeter(Ellipse2D.Double e);
public static double area(Ellipse2D.Double e);

that compute the area and the perimeter of the ellipse e . Add these
methods to a class Geometry . The challenging part of this assignment is
to find and implement an accurate formula for the perimeter. Why does it
make sense to use a static method in this case?

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΢΢ Exercise P8.8. Write methods

public static double angle(Point2D.Double p,
Point2D.Double q)
public static double slope(Point2D.Double p,
Point2D.Double q)

that compute the angle between the x-axis and the line joining two points,
measured in degrees, and the slope of that line. Add the methods to the