实验7面向对象编程

利用面向抽象的编程思想，计算各种柱体的体积。右图为该程序的 UML 类图。编写测试类 PillarTest，输出底为圆形、长方形、三角形的柱体体积。（在实验 3 的基础上修改）public abstract class Geometry private double r; Geometry(double r) this.r=r; /计算圆的面积 public double getArea(); /* *创建一个面向抽象类的的Pillar类 * */ public class Pillar private Geometry geometry; private double height; Pillar(Geometry geometry,double height) this.geometry=geometry; this.height=height; public double getVolumn() return geometry.getArea()*height; /* *创建一个Geometry的子类Rectangle * */ public class Rectangle extends Geometry double width; double height; Rectangle(double width,double height) this.width=width; this.height=height; Override public double getArea() return width*height; /* *创建一个Application计算柱体的体积 * */ public class Application public static void main(String args) Geometry geometry=new Rectangle(10.0,12.0); Pillar pillar=new Pillar(geometry,12.0); double volumn=pillar.getVolumn(); System.out.println(矩形底的柱体的体积：+volumn); 要求有一个abstract类，类名为Employee。Employee的子类有YearWorker、MonthWorker和WeekWorker。YearWorker对象按年薪领取薪水，MonthWorker按月领取薪水，WeekWorker按周领取薪水。Employee类有一个abstract方法：Public abstract earnings（）；子类必须重写父类的earnings（）方法，给出各自领取报酬的具体方式。有一个Company类，该类用Employee数组作为成员，Employee数组的单元可以是YearWorker对象的上转型对象、MonthWorker对象的上转型对象或WeekWorker对象的上转型对象。程序能输出Company对象一年需要支付的薪水总额。 package homework; class Company Employee em; /Employee作为成员 Company(Employee em) /构造函数 this.em=em; public static void main(String args) / TODO Auto-generated method stub Employee em=new Employee3; em0=new YearWorker(1,12000.0); /上转型对象 em1=new MonthWorker(11,8000.0); em2=new WeekWorker(40,1200.0); Company com=new Company(em); double sum; sum=em0.earnings()+em1.earnings()+em2.earnings(); System.out.println(总工资为:+sum); abstract class Employee abstract double earnings(); /抽象方法 class MonthWorker extends Employee int month; double monthSalary; MonthWorker(int m,double s) month=m; monthSalary=s; double earnings() return month*monthSalary; class WeekWorker extends Employee int week; double weekSalary; WeekWorker(int w,double s) week=w; weekSalary=s; double earnings() return week*weekSalary; class YearWorker extends Employee int year; double yearSalary; YearWorker(int y,double s) /工作年数，年工资 year=y; yearSalary=s; double earnings() /重写抽象方法 return year*yearSalary; 多态性是指统一的接口，不同的表现形式。在我们下面的例子中，有5个类。Game类是Football、Basketball、Popolong的父类，Games类使用前面4个类。Java根据动态绑定决定执行“更具体”的方法，即子类方法。1./Game.java2.3.package .uibe.oop;4.5.public class Game 6. protected void play()7. System.out.println(play game);8. 2.13./Football.java14.package .uibe.oop;15.16.public class Football extends Game 17.18. protected void play() 19. System.out.println(play football);20. super.play();21. 22. void f()23. play();24. 8.29./Basketball.java30.31.package .uibe.oop;32.33.public class Basketball extends Game34.35. protected void play() 36. System.out.println(play basketball);37. 1.42./Popolong.java43.44.package .uibe.oop;45.46.public class Popolong extends Game 47.48. protected void play() 49. System.out.println(play popolong);50. 4.55./Games.java56.57.package .uibe.oop;58.59.public class Games 60.61. public static void main(String args) 62. Game games = new Game10;63. games0 = new Basketball();64. games1 = new Football();65. games2 = new Popolong();66. 67. for(int i=0;igames.length;i+)68. if(gamesi!=null)69. gamesi.pl多态性是指统一的接口，不同的表现形式。在我们下面的例子中，有5个类。70.Game类是Football、Basketball、Popolong的父类，Games类使用前面4个类。71.Java根据动态绑定决定执行“更具体”的方法，即子类方法。72./Game.java73.74.package .uibe.oop;75.76.public class Game 77. protected void play()78. System.out.println(play game);79. 3.84./Football.java85.package .uibe.oop;86.87.public class Football extends Game 88.89. protected void play() 90. System.out.println(play football);91. super.play();92. 93. void f()94. play();95. 9.100./Basketball.java101.102.package .uibe.oop;103.104.public class Basketball extends Game105.106. protected void play() 107. System.out.println(play basketball);108. 12.113./Popolong.java114.115.package .uibe.oop;116.117.public class Popolong extends Game 118.119. protected void play() 120. System.out.println(play popolong);121. 25.126./Games.java127.128.package .uibe.oop;129.130.public class Games 131.132. public static void main(String args) 133. Game games = new Game10;134. ga