对象、继承、封装、多态、抽象类的组合应用

 1 /**
 2  * 定义一个Employee类，该类包含：
 3  *     private成员变量name,number,birthday，其中birthday 为MyDate类的对象；
 4  *    abstract方法earnings()；toString()方法输出对象的name,number和birthday。
 5  */
 6 public abstract class Employee {
 7     
 8     private String name;
 9     private int number;
10     private MyDate birthday;
11     
12     public Employee(String name, int number, MyDate birthday) {
13         this.name = name;
14         this.number = number;
15         this.birthday = birthday;
16     }
17 
18     abstract int earnings();
19 
20     @Override
21     public String toString() {
22         return "Employee [name=" + name + ", number=" + number + ", birthday="
23                 + birthday.toDateString() + "]";
24     }
25 
26     public String getName() {
27         return name;
28     }
29 
30     public void setName(String name) {
31         this.name = name;
32     }
33 
34     public int getNumber() {
35         return number;
36     }
37 
38     public void setNumber(int number) {
39         this.number = number;
40     }
41 
42     public MyDate getBirthday() {
43         return birthday;
44     }
45 
46     public void setBirthday(MyDate birthday) {
47         this.birthday = birthday;
48     }
49 }

 1 /**
 2  * MyDate类包含:
 3  *    private成员变量month,day,year；
 4  *    toDateString()方法返回日期对应的字符串：xxxx年xx月xx日
 5  */
 6 public class MyDate {
 7     
 8     private int month;
 9     private int day;
10     private int year;
11     
12     public MyDate(int month, int day, int year) {
13         this.month = month;
14         this.day = day;
15         this.year = year;
16     }
17 
18     public String toDateString(){
19         return year + "年" +
20                month + "月" +
21                day + "日";
22     }
23 
24     public int getMonth() {
25         return month;
26     }
27 
28     public void setMonth(int month) {
29         this.month = month;
30     }
31 
32     public int getDay() {
33         return day;
34     }
35 
36     public void setDay(int day) {
37         this.day = day;
38     }
39 
40     public int getYear() {
41         return year;
42     }
43 
44     public void setYear(int year) {
45         this.year = year;
46     }
47 }

 1 /**
 2  * 定义SalariedEmployee类继承Employee类，实现按月计算工资的员工处理。该类包括：
 3  * private成员变量weeklySalary；
 4  * 实现父类的抽象方法earnings(),该方法返回weeklySalary值；
 5  * toString()方法输出员工类型信息及员工的name，number,birthday。
 6  */
 7 public class SalariedEmployee extends Employee {
 8 
 9     private int weeklySalary;
10     
11     public SalariedEmployee(String name, int number, MyDate birthday,
12             int weeklySalary) {
13         super(name, number, birthday);
14         this.weeklySalary = weeklySalary;
15     }
16 
17     @Override
18     int earnings() {
19         return weeklySalary;
20     }
21     
22     @Override
23     public String toString() {
24         return "EmployeeType: SalariedEmployee, " + super.toString();
25     }
26 
27     public int getWeeklySalary() {
28         return weeklySalary;
29     }
30 
31     public void setWeeklySalary(int weeklySalary) {
32         this.weeklySalary = weeklySalary;
33     }
34 }

 1 /**
 2  * 参照SalariedEmployee类定义HourlyEmployee类，
 3  * 实现按小时计算工资的员工处理。该类包括：
 4  *    private成员变量wage和hour；
 5  *    实现父类的抽象方法earnings(),该方法返回wage*hour值；toString()方法输出员工类型信息及员工的name，number,birthday。
 6  */
 7 public class HourlyEmployee extends Employee {
 8 
 9     public HourlyEmployee(String name, int number, MyDate birthday, int wage,
10             int hour) {
11         super(name, number, birthday);
12         this.wage = wage;
13         this.hour = hour;
14     }
15 
16     private int wage;
17     private int hour;
18     
19     @Override
20     int earnings() {
21         return wage * hour;
22     }
23     
24     @Override
25     public String toString() { 
26         return "EmployeeType: HourlyEmployee, "+ super.toString();
27     }
28 
29     public int getWage() {
30         return wage;
31     }
32 
33     public void setWage(int wage) {
34         this.wage = wage;
35     }
36 
37     public int getHour() {
38         return hour;
39     }
40 
41     public void setHour(int hour) {
42         this.hour = hour;
43     }
44 }

 1 /**
 2  * 定义PayrollSystem类，创建Employee变量数组，该数组存放各类雇员对象的引用。
 3  * 利用循环结构，输入本月月份值，输出各个对象的类型,name,number,birthday,以及该对象生日。
 4  * 如果本月是某个Employee对象的生日，还要输出增加工资信息。
 5  */
 6 public class PayrollSystem {
 8     public static void main(String[] args) {
10         Employee [] emps = new Employee[5];
11         
12         emps[0] = new SalariedEmployee("Tom", 1001, new MyDate(4, 2, 1990), 200);
13         emps[1] = new SalariedEmployee("Jerry", 1002, new MyDate(5, 2, 1989), 300);
14         
15         emps[2] = new HourlyEmployee("Mike", 1003, new MyDate(6, 4, 1987), 100,  4);
16         emps[3] = new HourlyEmployee("Rose", 1004, new MyDate(4, 10, 1987), 200,  5);
17         emps[4] = new HourlyEmployee("Bob", 1005, new MyDate(8, 4, 1987), 300,  4);
18     
19         for(Employee emp: emps){
20             System.out.println(emp); 
21             
22             if(emp.getBirthday().getMonth() == 4){
23                 System.out.println("生日: 加工资 100 元");
24             }
25             System.out.println(); 
26         }
27     }
28 }