程序代码：

import java.util.Calendar;

public class Object {
    
    public interface AddtionalSalary {
        public abstract int getAddtionalSalary ();
    }
    
     public class Employee {
        String EmpName;//员工姓名
        int Month;//员工生日月份
        public int getAddtionalSalary (){
            return 0;//待
        }
        void setMonth(int Month){
            this.Month=Month;
        }
        int getMonth(){
            return Month;
        }
        public int getSalary (int Month){
            Calendar ca = Calendar.getInstance();
            int MonthNow = ca.get(Calendar.MONTH);
            this.Month = Month;
            //  实现生日加工资 100
            int salaryBir=0;
            if(Month==MonthNow)  salaryBir += 100;
            else salaryBir = 0;
            
            return salaryBir;
        }
    }
    
    class SalariedEmployee extends Employee{
        int MonthlyPay;
        
    }
    
    class HourlyEmployee extends Employee{
        int HourlyPay;
        int HourTime;
    }
    
    class SalesEmployee extends Employee {
        int Saleroom;
        int SalesPercentage;
    }
    
    class BasePlusSalesEmployee extends SalesEmployee {
        int BaseSalary;
    }
    
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        
        Employee Em = new Employee();
        Em.setMonth(10);
        System.out.println(getMonth());
        
    }

}