设计模式代码实战-组合模式

1、问题描述

小明所在的公司内部有多个部门，每个部门下可能有不同的子部门或者员工。

请你设计一个组合模式来管理这些部门和员工，实现对公司组织结构的统一操作。部门和员工都具有一个通用的接口，可以获取他们的名称以及展示公司组织结构。

输入示例

MyCompany

8

D HR

E HRManager

D Finance

E AccountantA

E AccountantB

D IT

E DeveloperA

E DeveloperB

输出示例

Company Structure:

MyCompany

HR

HRManager

Finance

AccountantA

AccountantB

IT

DeveloperA

DeveloperB

2、组合模式

它将对象组合成树状结构来表示"部分-整体"的层次关系。组合模式使得客户端可

以统⼀处理单个对象和对象的组合，⽽⽆需区分它们的具体类型。

类似树形结构，能够通过树形结构获取树中所有节点的信息。所有节点都有实现相同的接口

3、代码

import com.sun.java.accessibility.util.TopLevelWindowListener;

import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        String companyName=sc.nextLine();
        int number=Integer.parseInt(sc.nextLine());
        Company company=new Company(companyName);
        Department department=null;
        for(int i=0;i<number;i++){
          String s=sc.nextLine();
          String[] s1=s.split(" ");
          String a=s1[0];
          String b=s1[1];

          if(a.equals("D")){
                department=new Department(b);
                company.addDepartment(department);
          }else if(a.equals("E")){
                department.addEmployee(new Employee(b));
          }

        }
        company.Display(0);
    }
}

interface Component{
    void Display(int depth);
}

class Employee implements Component{
    private String name;
    public Employee(String name){
        this.name=name;
    }
    @Override
    public void Display(int depth) {
        for(int i=0;i<depth;i++){
            System.out.print("  ");
        }
        System.out.println(this.name);
    }
}

class Department implements  Component{
    List<Department> subDepartment;
    List<Employee> employees;
    String departmentName;
    public  Department(String name){
        subDepartment=new ArrayList<>();
        employees=new ArrayList<>();
        departmentName=name;
    }

    public void addEmployee(Employee e){
        employees.add(e);
    }

    public void addSubDepartment(Department d){
        subDepartment.add(d);
    }
    @Override
    public void Display(int depth) {
        for(int i=0;i<depth;i++){
            System.out.print("  ");
        }
        System.out.println(""+this.departmentName);
        if(!subDepartment.isEmpty()){
            for(int i=0;i<subDepartment.size();i++){
                subDepartment.get(i).Display(depth+1);
            }
        }
        if(!employees.isEmpty()){
            for(int i=0;i<employees.size();i++){
                employees.get(i).Display(depth+1);
            }
        }
    }
}

class Company implements Component{
    private String name;
    List<Department> departments;
    public Company(String name){
        this.name=name;
        departments=new ArrayList<>();
    }
    @Override
    public void Display(int depth) {
        System.out.println("Company Structure:");
        System.out.println(this.name);
        if(!departments.isEmpty()){
            for(int i=0;i<departments.size();i++){
                departments.get(i).Display(depth+1);
            }
        }
    }
    public void addDepartment(Department d){
        departments.add(d);
    }
}