中介模式

场景：mvc模式（其中的c，控制器就是一个中介者对象，m，v都和他打交道）；java.lang.reflect.Method#invoke()

例子：比如一个公司有市场部，开发部，财务部，之间的沟通就是通过总经理（中介者）来相互调用

Mediator.java（中介者接口）

public interface Mediator {void register(String dname,Department d);void command(String dname);}

President.java（实现中介者接口的具体类）

public class President implements Mediator {private Map<String,Department> map = new HashMap<String , Department>();@Overridepublic void command(String dname) {map.get(dname).selfAction();}@Overridepublic void register(String dname, Department d) {map.put(dname, d);}}

Deparment.java（同事类接口）

//同事类的接口public interface Department {void selfAction(); //做本部门的事情void outAction();  //向总经理发出申请}

Finacial.java（财务部）

public class Finacial implements Department {private Mediator m;  //持有中介者(总经理)的引用public Finacial(Mediator m) {super();this.m = m;m.register("finacial", this);}@Overridepublic void outAction() {System.out.println("汇报工作！没钱了，钱太多了！怎么花?");}@Overridepublic void selfAction() {System.out.println("数钱！");}}

Market.java（市场部）

public class Market implements Department {private Mediator m;  //持有中介者(总经理)的引用public Market(Mediator m) {super();this.m = m;m.register("market", this);}@Overridepublic void outAction() {System.out.println("汇报工作！项目承接的进度，需要资金支持！");m.command("finacial");}@Overridepublic void selfAction() {System.out.println("跑去接项目！");}}

Deparment.java（开发部）

public class Development implements Department {private Mediator m;  //持有中介者(总经理)的引用public Development(Mediator m) {super();this.m = m;m.register("development", this);}@Overridepublic void outAction() {System.out.println("汇报工作！没钱了，需要资金支持！");}@Overridepublic void selfAction() {System.out.println("专心科研，开发项目！");}}

测试

public class Client {public static void main(String[] args) {Mediator m = new President();Market   market = new Market(m);Development devp = new Development(m);Finacial f = new Finacial(m);market.selfAction();market.outAction();}}

简单的说就是中介者类存储所有同事类对象，所有同事类对象都有中介者类的引用，所有同事类就可以通过中介类相互调用其方法！