}
}
}
/** detach all observers */
public void unRegisterAll() {
synchronized(obserList) {
obserList.clear();
}
}
/** Ruturn the size of observers */
public int countObservers() {
synchronized(obserList) {
return obserList.size();
}
}
/**
* notify all observer （通知所有观察者，在子类中实现）
* @param objs
*/
public abstract void notifyObservers(Object... objs);
/**
* notify one certain observer （通知某一个确定的观察者）
* @param cls
* @param objs
*/
public abstract void notifyObserver(Class<?> cls, Object... objs);
/**
* notify one certain observer
* @param cls
* @param objs
*/
public abstract <T> void notifyObserver(T t, Object... objs);
}
//目标被观察者
public class ConcreteObservable extends Observable {
private static ConcreteObservable instance = null;
private ConcreteObservable() {}
public static synchronized ConcreteObservable getInstance() {
if (instance == null) {
instance = new ConcreteObservable();
}
return instance;
}
@Override
public <T> void notifyObserver(T t, Object... objs) {
// TODO Auto-generated method stub
if (t == null) throw new NullPointerException();
this.notifyObserver(t.getClass(), objs);
}
@Override
public void notifyObservers(Object... objs) {
// TODO Auto-generated method stub
for (Class<?> cls : obserList) {
this.notifyObserver(cls, objs);
}
}
@Override //通过java反射机制实现调用
public void notifyObserver(Class<?> cls, Object... objs) {
// TODO Auto-generated method stub
if (cls == null) throw new NullPointerException();
Method[] methods = cls.getDeclaredMethods();
for (Method method : methods) {
if (method.getName().equals("update")) {
try {
