һڹ۲Ҫõ observable ֪ͨʱʵ Observer ӿڵࡣ
interface java.util.Observer
.class interface Ljava/util/Observer;

ֻҪı observable ͵ô˷
void update(Observable o, Object arg)
invoke-interface {v0, v1, v2}, Ljava/util/Observer;->update(Ljava/util/Observable;Ljava/lang/Object;)V
