建造者

public class Factory {
private List<Sender> list=new LinkedList<Sender>();

public void produceEmailSender(int count){
for(int i=0;i<count;i++){
list.add(new EmailSender());
}
}
public void produceSmsSender(int count){
for(int i=0;i<count;i++){
list.add(new SmsSender());
}
}
}