/guava/android/guava/src/com/google/common/eventbus/SubscriberRegistry.java
this.bus = checkNotNull ( bus ) ;
@ElementTypesAreNonnullByDefault final class SubscriberRegistry { private final ConcurrentMap<Class<?>, CopyOnWriteArraySet<Subscriber>> subscribers = Maps.newConcurrentMap(); @Weak private final EventBus bus; SubscriberRegistry(EventBus bus) { <extra_id_0> } void register(Object listener) { Multimap<Class<?>, Subscriber> listenerMethods = findAllSubscribers(listener); for (Entry<Class<?>, Collection<Subscriber>> entry : listenerMethods.asMap().entrySet()) { Class<?> eventType = entry.getKey(); Collection<Subscriber> eventMethodsInListener = entry.getValue();