软件体系结构与设计模式第十一章中介者模式

1、第十二章第十二章 中介者模式中介者模式 2022-4-101中介者模式中介者模式 用一个中介对象来封装一系列的对象交互。中介者使各用一个中介对象来封装一系列的对象交互。中介者使各对象不需要显示地相互引用，从而使其耦合松散，而且对象不需要显示地相互引用，从而使其耦合松散，而且可以独立地改变它们之间的交互。可以独立地改变它们之间的交互。Mediator Pattern Define an object that encapsulates how a set of objects interact.Mediator promotes loose coupling by keeping objects

2、 from referring to each other explicitly, and it lets you vary their interaction independently.一一 、 概述概述 2022-4-103 中介者模式是封装一系列的对象交互的成中介者模式是封装一系列的对象交互的成熟模式，其关键是将对象之间的交互封装在熟模式，其关键是将对象之间的交互封装在称作中介者的对象中，中介者使各对象不需称作中介者的对象中，中介者使各对象不需要显示地相互引用，这些对象只包含中介者要显示地相互引用，这些对象只包含中介者的引用。当系统中某个对象需要和系统中另的引用。当系统中某个对象需要和

3、系统中另外一个对象交互时，只需将自己的请求通知外一个对象交互时，只需将自己的请求通知中介者即可。中介者即可。 二、二、中介者模式的结构与使用中介者模式的结构与使用2022-4-104模式的结构中包括四种角色：模式的结构中包括四种角色：中介者（中介者（MediatorMediator） 具体中介者（具体中介者（ConcreteMediatorConcreteMediator） 同事（同事（ColleagueColleague） 具体同事（具体同事（ConcreteColleagueConcreteColleague） 2022-4-105模式的模式的UMLUML类图类图 aConcreteMed

4、iatoraColleaguemediatoraColleaguemediatoraColleaguemediatoraColleaguemediatoraColleaguemediator模式的结构的描述与使用模式的结构的描述与使用 古代相互交战的A,B,C三方，想通过一个中介者调停之间的战火。A方委托调停者转达的信息是：“要求B方归还曾抢夺的100斤土豆，要求C方归还曾抢夺的20头牛”；B方委托调停者转达的信息是：“要求A方归还曾抢夺的10只鸡，要求C方归还曾抢夺的15匹马”；C方委托调停者转达的信息是：“要求A方归还曾抢夺的300斤小麦，要求B方归还曾抢夺的50头驴”。2022-4-10

5、81 1同事（同事（ColleagueColleague） : : Colleague.java Colleague.java public interface Colleaguepublic interface Colleague public void giveMess(String public void giveMess(String mess); mess); public void receiverMess(String public void receiverMess(String mess); mess); public void setName(String public v

6、oid setName(String name); name); public String getName public String getName();(); 注：本问题中，只需要一个具体中介者，我们并不需要一个中介者（注：本问题中，只需要一个具体中介者，我们并不需要一个中介者（MediatorMediator）接口）接口 。2022-4-1092 2具体中介者具体中介者（MediatorMediator） : : ConcreteMediator.javaConcreteMediator.java public class ConcreteMediatorpublic class Co

7、ncreteMediator ColleagueA colleagueA ColleagueA colleagueA; ; ColleagueB colleagueB ColleagueB colleagueB; ; ColleagueC colleagueC ColleagueC colleagueC; ; public void registerColleagueA(ColleagueA colleagueA public void registerColleagueA(ColleagueA colleagueA) this.colleagueA=colleagueA this.colle

8、agueA=colleagueA; ; public void registerColleagueB(ColleagueB colleagueB public void registerColleagueB(ColleagueB colleagueB) this.colleagueB=colleagueB this.colleagueB=colleagueB; ; public void registerColleagueC(ColleagueC colleagueC public void registerColleagueC(ColleagueC colleagueC) this.coll

9、eagueC=colleagueC this.colleagueC=colleagueC; ; public void deliverMess(Colleague colleague,String mess) if(colleague=colleagueA) if(mess.length=2) colleagueB.receiverMess(colleague.getName()+mess0); colleagueC.receiverMess(colleague.getName()+mess1); else if(colleague=colleagueB) if(mess.length=2)

10、colleagueA.receiverMess(colleague.getName()+mess0); colleagueC.receiverMess(colleague.getName()+mess1); else if(colleague=colleagueC) if(mess.length=2) colleagueA.receiverMess(colleague.getName()+mess0); colleagueB.receiverMess(colleague.getName()+mess1); 2022-4-10113 3具体同事（具体同事（ConcreteColleagueCon

11、creteColleague）_1: _1: ColleagueA.javaColleagueA.java public class ColleagueApublic class ColleagueA implements Colleague implements Colleague ConcreteMediator ConcreteMediator mediator; String name; mediator; String name; ColleagueA(ConcreteMediator ColleagueA(ConcreteMediator mediator) mediator) t

12、his.mediator=mediator; this.mediator=mediator; mediator.registerColleagueA(this mediator.registerColleagueA(this);); public void setName(String public void setName(String name) name) =name; =name; public String getName public String getName()() return name; return name; public void

13、 giveMess(String public void giveMess(String mess) mess) mediator.deliverMess(this,mess mediator.deliverMess(this,mess);); public void receiverMess(String public void receiverMess(String mess) mess) System.out.println(name System.out.println(name+收到的信息收到的信息:);:); System.out.println(t+mess System.out

14、.println(t+mess);); 2022-4-10123 3具体同事（具体同事（ConcreteColleagueConcreteColleague）_2: _2: ColleagueB.javaColleagueB.java public class ColleagueBpublic class ColleagueB implements Colleague implements Colleague ConcreteMediator ConcreteMediator mediator; mediator; String name; String name; ColleagueB(Co

15、ncreteMediator ColleagueB(ConcreteMediator mediator) mediator) this.mediator=mediator; this.mediator=mediator; mediator.registerColleagueB(this mediator.registerColleagueB(this);); public void setName(String public void setName(String name) name) =name; =name; public String getName

16、 public String getName()() return name; return name; public void giveMess(String public void giveMess(String mess) mess) mediator.deliverMess(this,mess mediator.deliverMess(this,mess);); public void receiverMess(String public void receiverMess(String mess) mess) System.out.println(name System.out.pr

17、intln(name+收到的信息收到的信息:);:); System.out.println(t+mess System.out.println(t+mess);); 2022-4-10133 3具体同事（具体同事（ConcreteColleagueConcreteColleague）_3: _3: ColleagueC.javaColleagueC.java public class ColleagueCpublic class ColleagueC implements Colleague implements Colleague ConcreteMediator ConcreteMedi

18、ator mediator; mediator; String name; String name; ColleagueC(ConcreteMediator ColleagueC(ConcreteMediator mediator) mediator) this.mediator=mediator; this.mediator=mediator; mediator.registerColleagueC(this mediator.registerColleagueC(this);); public void setName(String public void setName(String n

19、ame) name) =name; =name; public String getName public String getName()() return name; return name; public void giveMess(String public void giveMess(String mess) mess) mediator.deliverMess(this,mess mediator.deliverMess(this,mess);); public void receiverMess(String public void recei

20、verMess(String mess) mess) System.out.println(name System.out.println(name+收到的信息收到的信息:);:); System.out.println(t+mess System.out.println(t+mess);); 2022-4-10144 4应用应用 Application.javaApplication.java public class Application public class Application public static void main(String args public static

21、void main(String args) ConcreteMediator mediator=new ConcreteMediator ConcreteMediator mediator=new ConcreteMediator();(); ColleagueA colleagueA=new ColleagueA(mediator ColleagueA colleagueA=new ColleagueA(mediator);); ColleagueB colleagueB=new ColleagueB(mediator ColleagueB colleagueB=new Colleague

22、B(mediator);); ColleagueC colleagueC=new ColleagueC(mediator ColleagueC colleagueC=new ColleagueC(mediator);); colleagueA.setName(A colleagueA.setName(A国国);); colleagueB.setName(B colleagueB.setName(B国国);); colleagueC.setName(C colleagueC.setName(C国国);); String messA String messA=要求归还曾抢夺的要求归还曾抢夺的100100斤土豆斤土豆,要求归还曾抢夺的要求归还曾抢夺的2020头牛头牛; ; colleagueA.giveMess(messA colleagueA.giveMess(messA);); String messB String messB=要求归还曾抢夺的要求归还曾抢夺的1010只公鸡只公鸡,要求归还曾抢夺的要求归还曾抢夺的1515匹马匹马; colleagueB.giveMess(messB colleagueB.giveMess(messB);); String messC String messC=要