場景：算員工獎(jiǎng)金，各種獎(jiǎng)金，有個(gè)人銷售獎(jiǎng)，團(tuán)隊(duì)獎(jiǎng)，環(huán)比增加銷售獎(jiǎng)等等

1. 正常編碼

public class Prize {//計(jì)算某人在某段時(shí)間內(nèi)的獎(jiǎng)金，有些參數(shù)在演示中并不會(huì)使用， public double calcPrize(String user,Date begin,Date end){double prize = 0.0;//計(jì)算當(dāng)月業(yè)務(wù)獎(jiǎng)金，所有人都會(huì)計(jì)算prize = this.monthPrize(user, begin, end);//計(jì)算累計(jì)獎(jiǎng)金prize += this.sumPrize(user, begin, end);//需要判斷該人員是普通人員還是業(yè)務(wù)經(jīng)理，團(tuán)隊(duì)獎(jiǎng)金只有業(yè)務(wù)經(jīng)理才有if(this.isManager(user)){prize += this.groupPrize(user, begin, end);}return prize;}//計(jì)算某人的當(dāng)月業(yè)務(wù)獎(jiǎng)金，參數(shù)重復(fù)，就不再注釋了 private double monthPrize(String user, Date begin, Date end) {//計(jì)算當(dāng)月業(yè)務(wù)獎(jiǎng)金,按照人員去獲取當(dāng)月的業(yè)務(wù)額，然后再乘以3%double prize = TempDB.mapMonthSaleMoney.get(user) * 0.03;System.out.println(user+"當(dāng)月業(yè)務(wù)獎(jiǎng)金"+prize);return prize;}//計(jì)算某人的累計(jì)獎(jiǎng)金，參數(shù)重復(fù)，就不再注釋了 public double sumPrize(String user, Date begin, Date end) {//計(jì)算累計(jì)獎(jiǎng)金,其實(shí)這里應(yīng)該按照人員去獲取累計(jì)的業(yè)務(wù)額，然后再乘以0.1%//簡單演示一下，假定大家的累計(jì)業(yè)務(wù)額都是1000000元double prize = 1000000 * 0.001;System.out.println(user+"累計(jì)獎(jiǎng)金"+prize);return prize;} //判斷人員是普通人員還是業(yè)務(wù)經(jīng)理 private boolean isManager(String user){//應(yīng)該從數(shù)據(jù)庫中獲取人員對(duì)應(yīng)的職務(wù)//為了演示，簡單點(diǎn)判斷，只有王五是經(jīng)理if("王五".equals(user)){return true; }return false;}//計(jì)算當(dāng)月團(tuán)隊(duì)業(yè)務(wù)獎(jiǎng)，參數(shù)重復(fù)，就不再注釋了 public double groupPrize(String user, Date begin, Date end) {//計(jì)算當(dāng)月團(tuán)隊(duì)業(yè)務(wù)獎(jiǎng)金，先計(jì)算出團(tuán)隊(duì)總的業(yè)務(wù)額，然后再乘以1%，假設(shè)都是一個(gè)團(tuán)隊(duì)的double group = 0.0;for(double d : TempDB.mapMonthSaleMoney.values()){group += d;}double prize = group * 0.01;System.out.println(user+"當(dāng)月團(tuán)隊(duì)業(yè)務(wù)獎(jiǎng)金"+prize);return prize;} }//在內(nèi)存中模擬數(shù)據(jù)庫，準(zhǔn)備點(diǎn)測試數(shù)據(jù)，好計(jì)算獎(jiǎng)金 public class TempDB {private TempDB(){}//記錄每個(gè)人的月度銷售額，只用了人員，月份沒有用 public static Map<String,Double> mapMonthSaleMoney = new HashMap<String,Double>();static{//填充測試數(shù)據(jù)mapMonthSaleMoney.put("張三",10000.0);mapMonthSaleMoney.put("李四",20000.0);mapMonthSaleMoney.put("王五",30000.0);} }public class Client {public static void main(String[] args) {//先創(chuàng)建計(jì)算獎(jiǎng)金的對(duì)象Prize p = new Prize();//日期對(duì)象都沒有用上，所以傳null就可以了double zs = p.calcPrize("張三",null,null); System.out.println("==========張三應(yīng)得獎(jiǎng)金："+zs);double ls = p.calcPrize("李四",null,null);System.out.println("==========李四應(yīng)得獎(jiǎng)金："+ls); double ww = p.calcPrize("王五",null,null);System.out.println("==========王經(jīng)理應(yīng)得獎(jiǎng)金："+ww);} }

2. 模式介紹

動(dòng)態(tài)地給一個(gè)對(duì)象添加一些額外的職責(zé)。就增加功能來說，裝飾模式比生成子類更為靈活

//組件對(duì)象的接口，可以給這些對(duì)象動(dòng)態(tài)的添加職責(zé) public abstract class Component {//示例方法 public abstract void operation(); }//具體實(shí)現(xiàn)組件對(duì)象接口的對(duì)象 public class ConcreteComponent extends Component { public void operation() {//相應(yīng)的功能處理} }//裝飾器接口，維持一個(gè)指向組件對(duì)象的接口對(duì)象，并定義一個(gè)與組件接口一致的接口 public abstract class Decorator extends Component { protected Component component; //持有組件對(duì)象public Decorator(Component component) {this.component = component;} public void operation() {//轉(zhuǎn)發(fā)請(qǐng)求給組件對(duì)象，可以在轉(zhuǎn)發(fā)前后執(zhí)行一些附加動(dòng)作component.operation();} } //裝飾器的具體實(shí)現(xiàn)對(duì)象，向組件對(duì)象添加職責(zé) public class ConcreteDecoratorA extends Decorator {public ConcreteDecoratorA(Component component) {super(component);}//添加的狀態(tài) private String addedState; public void operation() {//調(diào)用父類的方法，可以在調(diào)用前后執(zhí)行一些附加動(dòng)作//在這里進(jìn)行處理的時(shí)候，可以使用添加的狀態(tài)super.operation();} }

總結(jié)

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