二十三种设计模式之中介者模式

中介者模式:用一个对象来封装一系列的对象交互

中介者使各个对象不需要显示的相互引用,从而使其耦合松散,而且可以独立的改变它们之间交互

使用场景 智能房屋

public interface Mediator {
public abstract void Register(String colleagueName,Colleague colleague);
public abstract void GetMessage(int sateChange,String colleagueName);
public abstract void sendMessage();
}

public abstract class Colleague {
private Mediator mediator;
public String name;

public Colleague(Mediator mediator, String name) {
super();
this.mediator = mediator;
this.name = name;
}

public Mediator GetMediator(){
return this.mediator;
}

public abstract void SendMessage(int stateChange);
}

public class Alarm extends Colleague{


public Alarm(Mediator mediator, String name) {
super(mediator, name);
mediator.Register(name, this);
}

public void SendAlarm(int stateChange){
SendMessage(stateChange);
}


@Override
public void SendMessage(int stateChange) {
this.GetMediator().GetMessage(stateChange, this.name);
}
}

public class CoffeeMachine extends Colleague {


public CoffeeMachine(Mediator mediator, String name) {
super(mediator, name);
mediator.Register(name, this);
}


@Override
public void SendMessage(int stateChange) {
this.GetMediator().GetMessage(stateChange, this.name);


}

public void startCoffee(){
System.out.println("It's time to startcoffee!");
}

public void FinishCoffee(){
System.out.println("After 5 minutes!");
System.out.println("Coffe is Ok!");
SendMessage(0);
}


}

public class Curtains extends Colleague{


public Curtains(Mediator mediator, String name) {
super(mediator, name);
mediator.Register(name, this);
}


@Override
public void SendMessage(int stateChange) {
this.GetMediator().GetMessage(stateChange, this.name);
}

public void UpCurtains(){
System.out.println("I am holding Up Curtains!");
}


}

public class TV extends Colleague{


public TV(Mediator mediator, String name) {
super(mediator, name);
mediator.Register(name, this);
}


@Override
public void SendMessage(int stateChange) {
this.GetMediator().GetMessage(stateChange, this.name);
}

public void StartTV(){
System.out.println("It's time to StartTv!");
}

public void StopTV(){
System.out.println("StopTv!");
}


}

public class ConcreteMediator implements Mediator{
private HashMap<String, Colleague> colleagueHashMap;
private HashMap<String, String> interMap;

public ConcreteMediator() {
colleagueHashMap = new HashMap<String, Colleague>();
interMap = new HashMap<String, String>();
}


@Override
public void Register(String colleagueName, Colleague colleague) {
colleagueHashMap.put(colleagueName, colleague);
if(colleague instanceof Alarm){
interMap.put("Alarm", colleagueName);
}else if(colleague instanceof CoffeeMachine){
interMap.put("CoffeeMachine", colleagueName);
}else if(colleague instanceof TV){
interMap.put("TV", colleagueName);
}else if(colleague instanceof Curtains){
interMap.put("Curtains", colleagueName);
}
}


@Override
public void GetMessage(int sateChange, String colleagueName) {
if(colleagueHashMap.get(colleagueName) instanceof Alarm){
if(sateChange == 0){
((CoffeeMachine)(colleagueHashMap.get(interMap.get("CoffeeMachine")))).startCoffee();
((TV)colleagueHashMap.get(interMap.get("TV"))).StartTV();
}else if(sateChange == 1){
((TV)colleagueHashMap.get(interMap.get("TV"))).StopTV();
}
}else if(colleagueHashMap.get(colleagueName) instanceof CoffeeMachine){
((Curtains)(colleagueHashMap.get(interMap.get("Curtains")))).UpCurtains();
}else if(colleagueHashMap.get(colleagueName) instanceof TV){

}else if(colleagueHashMap.get(colleagueName) instanceof Curtains){

}
}


@Override
public void sendMessage() {

}


}

public class MainTest {


public static void main(String[] args) {
Mediator mediator = new ConcreteMediator();

Alarm alarm = new Alarm(mediator, "alarm");
CoffeeMachine coffeeMachine = new CoffeeMachine(mediator, "coffeeMachine");
Curtains curtains = new Curtains(mediator, "curtains");
TV tv = new TV(mediator, "tv");
alarm.SendAlarm(0);
coffeeMachine.FinishCoffee();
alarm.SendAlarm(1);
}
}