设计模式 - 行为型模式 - 访问者模式

//员工类：抽象元素类
interface Employee {
public void accept(Department handler); //接受一个抽象访问者访问
}

//全职员工类：具体元素类
class FulltimeEmployee implements Employee {
private String name;
private double weeklyWage;
private int workTime;

public FulltimeEmployee(String name, double weeklyWage, int workTime) {
this.name = name;
this.weeklyWage = weeklyWage;
this.workTime = workTime;
}

public void setName(String name) {
this.name = name;
}

public void setWeeklyWage(double weeklyWage) {
this.weeklyWage = weeklyWage;
}

public void setWorkTime(int workTime) {
this.workTime = workTime;
}

public String getName() {
return (this.name);
}

public double getWeeklyWage() {
return (this.weeklyWage);
}

public int getWorkTime()

{
return (this.workTime);
}

public void accept(Department handler) {
handler.visit(this); //调用访问者的访问方法
}
}

//兼职员工类：具体元素类
class ParttimeEmployee implements Employee {
private String name;
private double hourWage;
private int workTime;

public ParttimeEmployee(String name, double hourWage, int workTime) {
this.name = name;
this.hourWage = hourWage;
this.workTime = workTime;
}

public void setName(String name) {
this.name = name;
}

public void setHourWage(double hourWage) {
this.hourWage = hourWage;
}

public void setWorkTime(int workTime) {
this.workTime = workTime;
}

public String getName() {
return (this.name);
}

public double getHourWage()

{
return (this.hourWage);
}

public int getWorkTime() {
return (this.workTime);
}

public void accept(Department handler) {
handler.visit(this); //调用访问者的访问方法
}
}

//部门类：抽象访问者类
abstract class Department {
//声明一组重载的访问方法，用于访问不同类型的具体元素
public abstract void visit(FulltimeEmployee employee);

public abstract void visit(ParttimeEmployee employee);
}

//财务部类：具体访问者类
class FADepartment extends Department {
//实现财务部对全职员工的访问
public void visit(FulltimeEmployee employee) {
int workTime = employee.getWorkTime();
double weekWage = employee.getWeeklyWage();
if (workTime > 40) {
weekWage = weekWage + (workTime - 40) * 100;
} else if (workTime < 40) {
weekWage = weekWage - (40 - workTime) * 80;
if (weekWage < 0) {
weekWage = 0;
}
}
System.out.println("正式员工" + employee.getName() + "实际工资为：" + weekWage + "元。");
}

//实现财务部对兼职员工的访问
public void visit(ParttimeEmployee employee) {
int workTime = employee.getWorkTime();
double hourWage = employee.getHourWage();
System.out.println("临时工" + employee.getName() + "实际工资为：" + workTime * hourWage + "元。");
}
}

//人力资源部类：具体访问者类
class HRDepartment extends Department {
//实现人力资源部对全职员工的访问
public void visit(FulltimeEmployee employee) {
int workTime = employee.getWorkTime();
System.out.println("正式员工" + employee.getName() + "实际工作时间为：" + workTime + "小时。");
if (workTime > 40) {
System.out.println("正式员工" + employee.getName() + "加班时间为：" + (workTime - 40) + "小时。");
} else if (workTime < 40) {
System.out.println("正式员工" + employee.getName() + "请假时间为：" + (40 - workTime) + "小时。");
}
}

//实现人力资源部对兼职员工的访问
public void visit(ParttimeEmployee employee) {
int workTime = employee.getWorkTime();
System.out.println("临时工" + employee.getName() + "实际工作时间为：" + workTime + "小时。");
}
}

//员工列表类：对象结构
class EmployeeList {
//定义一个集合用于存储员工对象
private ArrayList<Employee> list = new ArrayList<Employee>();

public void addEmployee(Employee employee) {
list.add(employee);
}

//遍历访问员工集合中的每一个员工对象
public void accept(Department handler) {
for (Object obj : list) {
((Employee) obj).accept(handler);
}
}
}

class Client {
public static void main(String args[]) {
EmployeeList list = new EmployeeList();
Employee fte1, fte2, fte3, pte1, pte2;
fte1 = new FulltimeEmployee("张无忌", 3200.00, 45);
fte2 = new FulltimeEmployee("杨过", 2000.00, 40);
fte3 = new FulltimeEmployee("段誉", 2400.00, 38);
pte1 = new ParttimeEmployee("洪七公", 80.00, 20);
pte2 = new ParttimeEmployee("郭靖", 60.00, 18);
list.addEmployee(fte1);
list.addEmployee(fte2);
list.addEmployee(fte3);
list.addEmployee(pte1);
list.addEmployee(pte2);
Department dep;
dep = (Department) XMLUtil.getBean();
list.accept(dep);
}
}