package asf;
interface Listener {
}
abstract class Event {
//public abstract void happen();
public abstract int getId();
}
class RainEvent extends Event {
private static final int id = 1;
/*public void happen() {
// TODO Auto-generated method stub
System.out.println("raining");
}*/
public String toString(){
return "raining";
}
public int getId() {
// TODO Auto-generated method stub
return id;
}
}
class AlarmEvent extends Event {
private static final int id = 3;
/*public void happen() {
// TODO Auto-generated method stub
System.out.println("Alarming");
}*/
public String toString(){
return "Alarming";
}
public int getId() {
// TODO Auto-generated method stub
return id;
}
}
class BroadcastEvent extends Event {
private static final int id = 2;
public int getId() {
// TODO Auto-generated method stub
return id;
}
/*public void happen() {
// TODO Auto-generated method stub
System.out.println("Broadcasting");
}*/
public String toString(){
return "Broadcasting";
}
}
interface RainListener extends Listener {
public void rain(Event e);
}
interface RadioListener extends Listener {
public void broadcast(Event e);
}
interface ClockListener extends Listener {
public void alarm(Event e);
}
class ListenerCaster implements RainListener, RadioListener, ClockListener {
Listener l1;
Listener l2;
ListenerCaster(Listener l1, Listener l2) {
this.l1 = l1;
this.l2 = l2;
}
public void rain(Event e) {
// TODO Auto-generated method stub
if(l1!=null){
((RainListener) l1).rain(e);
}
if(l2!=null){
((RainListener) l2).rain(e);
}
}
public void broadcast(Event e) {
// TODO Auto-generated method stub\
if(l1!=null){
((RadioListener) l1).broadcast(e);}
if(l2!=null){
((RadioListener) l2).broadcast(e);}
}
public void alarm(Event e) {
// TODO Auto-generated method stub
if(l1!=null){
((ClockListener) l1).alarm(e);}
if(l2!=null){
((ClockListener) l2).alarm(e);}
}
}
class TheNotifiedObject {
RainListener rl;
RadioListener ral;
ClockListener cl;
public void addRainListener(RainListener rl) {
this.rl = new ListenerCaster(this.rl, rl);
}
public void addRadioListener(RadioListener ral) {
this.ral = new ListenerCaster(this.ral, ral);
}
public void addClockListener(ClockListener cl) {
this.cl = new ListenerCaster(this.cl, cl);
}
protected void processEvent(Event e) {
switch (e.getId()) {
case 1:
if(ral!=null){
rl.rain(e);
}
break;
case 2:
if(ral!=null){
ral.broadcast(e);}
break;
case 3:
if(cl!=null){
cl.alarm(e);}
break;
}
}
}
public class TheNotifiedObjectA extends TheNotifiedObject {
TheNotifiedObjectA() {
addClockListener(new ClockListener() {
public void alarm(Event e) {
// TODO Auto-generated method stub
System.out.println(e);
}
});
addRainListener(new RainListener() {
public void rain(Event e) {
// TODO Auto-generated method stub
System.out.println(e);
}
});
addRadioListener(new RadioListener() {
public void broadcast(Event e) {
// TODO Auto-generated method stub
System.out.println(e);
}
});
}
public static void main(String[] args){
Event e1=new AlarmEvent();
Event e2=new RainEvent();
Event e3=new BroadcastEvent();
TheNotifiedObjectA k=new TheNotifiedObjectA();
k.processEvent(e1);
k.processEvent(e2);
k.processEvent(e3);
}
}
