1、對Java策略模式的理解主要是通過一個實例來理解：封裝商場鞋子的打折策略。分析：商場鞋子打折活動，我們簡單概括為雙休打折和節日打折（其他 特定日打折自己寫）。雙休打折和節日打折這 2類打折活動的具體規則 一般都不會一樣，通過封裝打折策略，來增強程序的可擴展性。也就是 說，下次商場有其他的 打折策略時，只需添加一個該 打折策略的類即可,實現對原來代碼修改量最少，符合開閉的原則。代碼:1. Shoe.java 文件:Public class Shoe implements IShopCutprivatedouble value;p ublicShoe( double value) this.val

2、ue = value;p ublicdouble getValue() retur nvalue;p ublicvoid setValue( double cut price) this .value = cut price;Overridepublicdouble shopCut() return new FestivalCut() .cut( this );2. ISho pCut.java文件p ublicin terface ISho pCut double shopCut();3.雙休日打折 WeekendCut.java 文件:public class WeekendCut p r

3、ivatedouble cut price;publicdouble getCutpriceO return cut price;publicdouble cut(Shoe s)if (s.getValue() > 300 )cut price = s.getValue()*80/100;else if (s.getValue() > 200 )cut price = s.getValue()*85/100;else if (s.getValue() > 150 )cut price = s.getValue()*95/100;elsecut price = s.getVal

4、ue();s.setValue(cut price);return cut price;4.節日打折 FestivalCut.java 文件:publicclass FestivalCut p rivatedouble cut price;publicdouble getCutprice() return cut price;publicdouble cut(Shoe s)if (s.getValue() > 1000 )cut price = s.getValue()*60/100;else if (s.getValue() > 500 )cut price = s.getVal

5、ue()*85/100;else if (s.getValue() > 300 )cut price = s.getValue()*95/100;elsecut price = s.getValue();s.setValue(cut price);return cut price;5.客戶端測試代碼Test.java文件:publicclass Test Publicstatic void main(String args) System. out .println(”打折前的價格：” + price);double price = 360;Shoe sh = new Shoe( price);p rice = sh.sho pCut();System. out .println(”打折后的價格：” + price);注：整個程序修改部分只是在Shoe.java文