28.按要求编写一个Java应用程序:
(1)定义一个类,描述一个矩形,包含有长、宽两种属性,和计算面积方法。
(2)编写一个类,继承自矩形类,同时该类描述长方体,具有长、宽、高属性,
和计算体积的方法。
(3)编写一个测试类,对以上两个类进行测试,创建一个长方体,定义其长、
宽、高,输出其底面积和体积。
package zuoye; public class juxing { public double height; public double width; public double getHeight() { return height; } public void setHeight(double height) { this.height = height; } public double getWidth() { return width; } public void setWidth(double width) { this.width = width; } public juxing() { super(); } public double area() { return this.height*this.width; } }
package zuoye; public class lifangti extends juxing { private double high; public double getHigh() { return high; } public void setHigh(double high) { this.high = high; } lifangti(double height,double width,double high) { super(); high=this.high; } public double lifangti() { return high*height*width; } }
package zuoye; public class ceshijuxinglifangti { public static void main(String[] args) { juxing j =new juxing(); lifangti l =new lifangti(2, 3, 4); System.out.println("体积"+l.lifangti()); System.out.println("面积"+j.area()); } }