observerclient.java

designpatterns for aop

package designpatterns.observer.java;

import java.util.ArrayList;
import java.util.List;


public class ObserverClient {

	public static void main(String[] args) {
		BillingService basicBilling = new BillingService();
		BillingService premiumBilling = new BillingService();
		
		Song song = new Song("Kris Kringle Was A Cat Thief");
		song.addObserver(basicBilling);
		
		
		Song song2 = new Song("Rock n Roll McDonald's");
		song2.addObserver(basicBilling);
		//this song is billed by two services,
		//perhaps the label demands an premium for online access?
		song2.addObserver(premiumBilling);
		
		Playlist favorites = new Playlist("Favorites");
		favorites.addObserver(basicBilling);
		
		List songs = new ArrayList();
		songs.add(song);
		songs.add(song2);
		favorites.setSongs(songs);
		
		favorites.play();
		
		song.showLyrics();
	}
}