标签：设计模式 建造者模式
快餐套餐一般含有主食、饮料、点心三部分组成，KFC快餐套餐与Mcdonald快餐套餐的生成过程大致都是一样的。每份套餐由主食、饮料、点心三部分组成，当每部分具体的食品可能不同，如主食可能是鸡肉卷、汉堡等，即对象的各组成部分可能因为需求的变化面临剧烈的变化。
MealBuilder：快餐套餐的生产步骤的抽象接口
KFCMealBuilder：KFC快餐套餐的具体生产步骤
McDonalMealBuilder：Mcdonalds快餐套餐的具体生产步骤
Waiter：服务员，控制快餐套餐的生产过程
Meal：快餐套餐的基本属性
Meal产品信息类：
#ifndef MEAL_H
#define MEAL_H
#include <iostream>
#include <string>
using namespace std;
class Meal
{
public:
void setFood(const string& food)
{
m_food = food;
cout << "add a "<< food << endl;
}
void setDrink(const string& drink)
{
m_drink = drink;
cout << "add a "<< drink << endl;
}
void setNosh(const string& nosh)
{
m_nosh = nosh;
cout << "add a "<< nosh << endl;
}
private:
string m_food;
string m_drink;
string m_nosh;
};
#endif // MEAL_H
MealBuilder抽象建造者：
#ifndef MEALBUILDER_H
#define MEALBUILDER_H
#include "Meal.h"
class MealBuilder
{
public:
virtual void buildFood() = 0;
virtual void buildDrink() = 0;
virtual void buildNosh() = 0;
virtual Meal* getMeal() = 0;
};
#endif // MEALBUILDER_H
KFCMealBuilder具体建造者：
#ifndef KFCMEALBUILDER_H
#define KFCMEALBUILDER_H
#include <string>
#include <iostream>
#include "MealBuilder.h"
using namespace std;
class KFCMealBuilder : public MealBuilder
{
public:
KFCMealBuilder()
{
m_meal = new Meal();
cout << "KFC FastFood is ready..." << endl;
}
virtual void buildFood()
{
m_meal->setFood("Dragon Twister");
}
virtual void buildDrink()
{
m_meal->setDrink("Coca-Cola");
}
virtual void buildNosh()
{
m_meal->setNosh("Popcorn chicken");
}
virtual Meal* getMeal()
{
return m_meal;
}
private:
Meal* m_meal;
};
#endif // KFCMEALBUILDER_H
McDonalMealBuilder具体建造者：
#ifndef MCDONALMEALBUILDER_H
#define MCDONALMEALBUILDER_H
#include "MealBuilder.h"
class McDonalMealBuilder : public MealBuilder
{
public:
McDonalMealBuilder()
{
m_meal = new Meal();
cout << "McDonal FastFood is ready..." << endl;
}
virtual void buildFood()
{
m_meal->setFood("hamburger");
}
virtual void buildDrink()
{
m_meal->setDrink("Coca-Cola");
}
virtual void buildNosh()
{
m_meal->setDrink("Chips");
}
virtual Meal* getMeal()
{
return m_meal;
}
private:
Meal* m_meal;
};
#endif // MCDONALMEALBUILDER_H
指挥者Waiter类:
#ifndef WAITER_H
#define WAITER_H
#include <string>
#include <iostream>
#include "MealBuilder.h"
using namespace std;
class Waiter
{
public:
Waiter(MealBuilder* builder)
{
m_builder = builder;
}
void createMeal()
{
m_builder->buildFood();
m_builder->buildDrink();
m_builder->buildNosh();
cout << "Fast Food is done." << endl;
}
private:
MealBuilder* m_builder;
};
#endif // WAITER_H
客户端调用程序：
#include "Waiter.h"
#include "KFCMealBuilder.h"
#include "McDonalMealBuilder.h"
int main()
{
Waiter McDonalWaiter(new McDonalMealBuilder());
McDonalWaiter.createMeal();
Waiter KFCWaiter(new KFCMealBuilder());
KFCWaiter.createMeal();
return 0;
}
公司员工工资的计算一般是：底薪+奖金-税金，但研发人员底薪分为一级8000、二级6000、三级4000三个等级，销售人员的底薪则统一为3000，奖金则由经理根据业绩考核发放。税金则根据奖金和底薪的数额进行计算。由此看出工资的计算方式是比较稳定的构建算法，但对工资的每一部分都会根据不同的情况产生不同的算法，如何将客户端与变化剧烈的底薪、奖金和税金计算方式分离，比较适合用建造者模式。
Income产品：
#ifndef INCOME_H
#define INCOME_H
//产品
class Income
{
public:
Income()
{}
//研发人员底薪设置接口
void setBasicSalary(char type)
{
if(type == ‘A‘)
m_basicSalary = 4000;
else if(type == ‘B‘)
m_basicSalary = 6000;
else if(type == ‘C‘)
m_basicSalary = 8000;
}
//销售人员底薪社会子接口
void setBasicSalary(unsigned int basic)
{
m_basicSalary = basic;
}
unsigned int getBasicSalary()
{
return m_basicSalary;
}
void setBonus(double bonus)
{
m_bonus = bonus;
}
unsigned int getBonus()
{
return m_bonus;
}
unsigned int getIncomeTax()
{
//税金根据底薪和奖金总额确定税率
unsigned total = m_basicSalary + m_bonus;
if(total < 10000)
m_incomeTax = total * 0.1;
else
m_incomeTax = total * 0.15;
return m_incomeTax;
}
private:
unsigned int m_basicSalary;//底薪
unsigned int m_bonus;//奖金
unsigned int m_incomeTax;//税金
};
#endif // INCOME_H
Post抽象建造者：
#ifndef POST_H
#define POST_H
//Builder抽象类
class Post
{
public:
virtual double buildBasicSalary() = 0;
virtual double buildBonus() = 0;
virtual double buildIncomeTax() = 0;
virtual void setBonus(double bonus) = 0;
};
#endif // POST_H
Developer具体建造者：
#ifndef DEVELOPER_H
#define DEVELOPER_H
#include "Income.h"
#include "Post.h"
//具体Builder
class Developer : public Post
{
public:
Developer(char level)//分为三个等级
{
m_income = new Income();
m_income->setBasicSalary(level);
}
virtual double buildBasicSalary()
{
double basic = 0;
basic = m_income->getBasicSalary();
return basic;
}
virtual double buildBonus()
{
double number = 0;
number = m_income->getBonus();
return number;
}
void setBonus(double bonus)
{
m_income->setBonus(bonus);
}
virtual double buildIncomeTax()
{
double n = 0;
n = m_income->getIncomeTax();
return n;
}
private:
Income* m_income;
};
#endif // DEVELOPER_H
SalesMan具体建造者：
#ifndef SALESMAN_H
#define SALESMAN_H
#include "Post.h"
#include "Income.h"
//具体Builder
class SalesMan : public Post
{
public:
SalesMan()//销售人员无等级
{
m_income = new Income();
m_income->setBasicSalary(3000u);
}
double buildBasicSalary()
{
double basic = 0;
basic = m_income->getBasicSalary();
return basic;
}
double buildBonus()
{
double number = 0;
number = m_income->getBonus();
return number;
}
void setBonus(double bonus)
{
m_income->setBonus(bonus);
}
double buildIncomeTax()
{
double n = 0;
n = m_income->getIncomeTax();
return n;
}
private:
Income* m_income;
};
#endif // SALESMAN_H
Accountant指挥者类：
#ifndef ACCOUNTANT_H
#define ACCOUNTANT_H
#include "Post.h"
#include <iostream>
using namespace std;
//Director指挥者类
class Accountant
{
public:
//财务，指定要具体计算谁的薪水
Accountant(Post* post)
{
m_post = post;
}
double computeSalary()//计算薪水
{
double basic = m_post->buildBasicSalary();
double bonus = m_post->buildBonus();
double tax = m_post->buildIncomeTax();
double income = basic + bonus - tax;
cout << "Salary: " << income<< endl;
return income;
}
private:
Post* m_post;
};
#endif // ACCOUNTANT_H
Manager管理者类：
#ifndef MANAGER_H
#define MANAGER_H
#include "Post.h"
//辅助类，负责考核员工的业绩并确定发放的奖金数额
class Manager
{
public:
Manager(Post* post)
{
m_post = post;
}
//根据业绩确定员工的奖金数额
void setBonus(double bonus)
{
m_post->setBonus(bonus);
}
private:
Post* m_post;
};
#endif // MANAGER_H
客户调用程序：
#include <iostream>
#include "Manager.h"
#include "Accountant.h"
#include "Developer.h"
#include "SalesMan.h"
using namespace std;
int main()
{
Developer developer1(‘C‘);
Manager manager1(&developer1);
manager1.setBonus(5000);
Accountant* accountant1 = new Accountant(&developer1);
accountant1->computeSalary();
Developer developer2(‘A‘);
Manager manager2(&developer2);
manager2.setBonus(3000);
Accountant* accountant2 = new Accountant(&developer2);
accountant2->computeSalary();
SalesMan sale;
Manager manager3(&sale);
manager3.setBonus(12000);
Accountant* accountant3 = new Accountant(&sale);
accountant3->computeSalary();
delete accountant1,accountant2,accountant3;
return 0;
}
本文出自 “生命不息，奋斗不止” 博客，谢绝转载！
标签：设计模式 建造者模式
原文地址：http://9291927.blog.51cto.com/9281927/1970094
