Question

①用java编写物体的体积和表面积计算的程序，并用立方体和球体测试 ②

用有层次结构的包管理物体体积和表面积计算的程序

Answer 1

/*
* Geometry.java
*/

public class Geometry {
public static int instance = 0;
public Geometry () {
instance++;
}
public static double calculateRectangle(double width, double height) {
return width * height;
}

public static double calculateCube(double width, double height, double length) {
return width * height * length;
}

public static double calculateSphere (double radius) {
return (4 * Math.PI * radius * radius * radius) /3;
}

public static void main(String[] args) {
System.out.println(" 1 " + calculateRectangle(4, 5));
System.out.println(" Instance = " + instance);
System.out.println(" 2 " + calculateCube(4, 5, 6));
System.out.println(" Instance = " + instance);
System.out.println(" 3 " + calculateSphere(3));
System.out.println(" Instance = " + instance);
}
}