【大话设计模式】——外观模式Facade

1、外观模式：
    为子系统中一组提供一种一致的界面，此模式定义一个高层接口，该接口使得这一子系统更加容易。
2、UML图：应该是聚合关系

3、示例代码

#include <iostream>

using namespace std;

class stock_one
{
public:
    void sell()
    {
        cout<<"sell out stock1\n";
    }
    void buy()
    {
        cout<<"buy stock1\n";
    }
};
class stock_two
{
public:
    void sell()
    {
        cout<<"sell out stock2\n";
    }
    void buy()
    {
        cout<<"buy stock2\n";
    }
};

class fund
{
public:
    fund()
    {
        one = new stock_one();
        two = new stock_two();
    }
    void sell()
    {
        one->sell();
        two->sell();
    }
    void buy()
    {
        one->buy();
        two->buy();
    }
private:
    stock_one* one;
    stock_two* two;
};

void main()
{
    cout<<"hello "<<endl;
    fund* fund_stock = new fund();
    fund_stock->sell();
}