公司员工类延伸，管理者类
import java.util.*;public class ManagerTest{public static void main(String args[]){Manager boss=new Manager("Cal Cracker",80000,1987,12,15);boss.setBonus(5000);Employee[] staff=new Employee[3];staff[0]=boss;staff[1]=new Employee("Harry Hacker",50000,1989,10,1);staff[2]=new Employee("David",4000,1990,2,23);for(Employee e:staff){System.out.println("name="+e.getName()+",salary="+e.getSalary());}}}class Employee{public Employee(String n,double s,int year,int month,int day){name=n;salary=s;GregorianCalendar calendar=new GregorianCalendar(year,month-1,day);hireDay=calendar.getTime();}public String getName(){return name;}public double getSalary(){return salary;}public Date getHireDay(){return hireDay;}public void raiseSalary(double byPercent){double raise=salary*byPercent/100;salary+=raise;}private String name;private double salary;private Date hireDay;}class r extends Employee{public Manager(String n,double s,int year,int month,int day){super(n,s,year,month,day);bonus=0;}public double getSalary(){double baseSalary=super.getSalary();return baseSalary+bonus;}public void setBonus(double b){bonus=b;}private double bonus;}