2. 结构型模式 (6) 组合模式

2. 结构型模式 (6) 组合模式

组合模式（Composite Pattern），又叫部分整体模式，是用于把一组相似的对象当作一个单一的对象。组合模式依据树形结构来组合对象，用来表示部分以及整体层次。

这种模式创建了一个包含自己对象组的类。该类提供了修改相同对象组的方式。

1. 组合模式

package com.andrew.pattern0206.composite.model01;
import java.util.ArrayList;
import java.util.List;
public class Employee {
    private String name;
    private String dept;
    private int salary;
    private List<Employee> subordinates;
    public Employee(String name,String dept, int sal) {
        this.name = name;
        this.dept = dept;
        this.salary = sal;
        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 : "+ dept + ", salary :" + salary+" ]");
    }
}

package com.andrew.pattern0206.composite.model01;
/**
 * 1. 组合模式
 * 
 * @author andrew
 * @date 2017/07/18
 */
public class Client {
    public static void main(String[] args) {
        Employee CEO = new Employee("John","CEO", 30000);
        Employee headSales = new Employee("Robert","Head Sales", 20000);
        Employee headMarketing = new Employee("Michel","Head Marketing", 20000);
        Employee clerk1 = new Employee("Laura","Marketing", 10000);
        Employee clerk2 = new Employee("Bob","Marketing", 10000);
        Employee salesExecutive1 = new Employee("Richard","Sales", 10000);
        Employee salesExecutive2 = new Employee("Rob","Sales", 10000);
        CEO.add(headSales);
        CEO.add(headMarketing);
        headSales.add(salesExecutive1);
        headSales.add(salesExecutive2);
        headMarketing.add(clerk1);
        headMarketing.add(clerk2);
        System.out.println(CEO);
        for (Employee headEmployee : CEO.getSubordinates()) {
            System.out.println(headEmployee);
            for (Employee employee : headEmployee.getSubordinates()) {
                System.out.println(employee);
            }
        }
    }
}
运行结果：
Employee :[ Name : John, dept : CEO, salary :30000 ]
Employee :[ Name : Robert, dept : Head Sales, salary :20000 ]
Employee :[ Name : Richard, dept : Sales, salary :10000 ]
Employee :[ Name : Rob, dept : Sales, salary :10000 ]
Employee :[ Name : Michel, dept : Head Marketing, salary :20000 ]
Employee :[ Name : Laura, dept : Marketing, salary :10000 ]
Employee :[ Name : Bob, dept : Marketing, salary :10000 ]