Java设计模式 - 组合模式
组合模式是结构型模式，因为它创建了一组对象的树结构。
组合模式将一组对象视为单个对象。
组合模式使用一个类来表示树结构。
在组合模式中，我们创建一个包含自己对象的类的组。
例子
以下代码使用Employee类来演示组合模式。
import java.util.ArrayList;
import java.util.List;
class Employee {
private String name;
private String title;
private List<Employee> subordinates;
public Employee(String name,String title) {
this.name = name;
this.title = title;
subordinates = new ArrayList<Employee>();
}
public void add(Employee e) {
subordinates.add(e);
}
public void remove(Employee e) {
subordinates.remove(e);
}
public List<Employee> getSubordinates(){
return subordinates;
}
public String toString(){
return "Employee :[ Name : "+ name
+", dept : "+ title +subordinates +" ]";
}
}
public class Main {
public static void main(String[] args) {
Employee CEO = new Employee("John","CEO");
Employee headSales = new Employee("Rob","Sales");
Employee headMarketing = new Employee("Mike","Marketing");
Employee programmer1 = new Employee("Lili","Programmer");
Employee programmer2 = new Employee("Bob","Programmer");
Employee tester1 = new Employee("Jack","Tester");
Employee tester2 = new Employee("Tom","Tester");
CEO.add(headSales);
CEO.add(headMarketing);
headSales.add(tester1);
headSales.add(tester2);
headMarketing.add(programmer1);
headMarketing.add(programmer2);
//print all employees of the organization
System.out.println(CEO);
for (Employee headEmployee : CEO.getSubordinates()) {
System.out.println(headEmployee);
for (Employee employee : headEmployee.getSubordinates()) {
System.out.println(employee);
}
}
}
}
上面的代码生成以下结果。
