Swift设计模式之装饰模式

来源：互联网发布：java jdk安装编辑：程序博客网时间：2024/06/08 06:19
转自
Swift设计模式
原文
Design-Patterns-In-Swift
// 装饰模式// 百度百科：在不必改变原类文件和使用继承的情况下，动态地扩展一个对象的功能。它是通过创建一个包装对象，也就是装饰来包裹真实的对象// 设计模式分类：结构型模式/** *  咖啡接口 */protocol Coffee {    /**     价格     - returns: 价格     */    func getCost() -> Double    /**     原料     - returns: 原料     */    func getIngredients() -> String}/// 简单咖啡实现class SimpleCoffee: Coffee {    func getCost() -> Double {        return 1.0    }    func getIngredients() -> String {        return "Coffee"    }}/// 咖啡装饰接口class CoffeeDecorator: Coffee {    private let decoratedCoffee: Coffee    private let ingredientSeparator: String = ", "    required init(decoratedCoffee: Coffee) {        self.decoratedCoffee = decoratedCoffee    }    func getCost() -> Double {        return decoratedCoffee.getCost()    }    func getIngredients() -> String {        return decoratedCoffee.getIngredients()    }}/// 牛奶装饰实现class Milk: CoffeeDecorator {    required init(decoratedCoffee: Coffee) {        super.init(decoratedCoffee: decoratedCoffee)    }    override func getCost() -> Double {        return super.getCost() + 0.5    }    override func getIngredients() -> String {        return super.getIngredients() + ingredientSeparator + "Milk"    }}/// whip装饰实现class WhipCoffee: CoffeeDecorator {    required init(decoratedCoffee: Coffee) {        super.init(decoratedCoffee: decoratedCoffee)    }    override func getCost() -> Double {        return super.getCost() + 0.7    }    override func getIngredients() -> String {        return super.getIngredients() + ingredientSeparator + "Whip"    }}var someCoffee: Coffee = SimpleCoffee() // 简单咖啡print("Cost : \(someCoffee.getCost()); Ingredients: \(someCoffee.getIngredients())")var milkCoffee = Milk(decoratedCoffee: someCoffee) // 装饰了牛奶的咖啡print("Cost : \(milkCoffee.getCost()); Ingredients: \(milkCoffee.getIngredients())")var whipCoffee = WhipCoffee(decoratedCoffee: milkCoffee) // 装饰了whip和牛奶的咖啡print("Cost : \(whipCoffee.getCost()); Ingredients: \(whipCoffee.getIngredients())")
0 0