37 lines
780 B
C++
37 lines
780 B
C++
/**
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* @name 装饰器模式
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* @brief: 动态添加职责
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* @note 场景：流处理（加密/压缩装饰）、GUI 组件增强
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*/
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class Coffee {
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public:
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virtual double cost() = 0;
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};
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class SimpleCoffee : public Coffee {
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public:
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double cost() override { return 6.9; }
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};
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class CoffeeDecorator : public Coffee {
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protected:
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Coffee* coffee;
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public:
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CoffeeDecorator(Coffee* c) : coffee(c) {}
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};
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class MilkDecorator : public CoffeeDecorator {
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public:
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MilkDecorator(Coffee* c) : CoffeeDecorator(c) {}
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double cost() override {
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return coffee->cost() + 0.5; // 增加牛奶费用
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}
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};
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// 使用
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int main()
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{
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Coffee* coffee = new SimpleCoffee();
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coffee = new MilkDecorator(coffee); // 动态装饰
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coffee->cost(); // 基础 + 牛奶
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} |