com.github.zhengframework.eventbus.EventSubscribersInfo Maven / Gradle / Ivy
package com.github.zhengframework.eventbus;
import com.google.common.eventbus.EventBus;
import com.google.common.eventbus.SubscriptionIntrospector;
import java.util.Set;
import javax.inject.Inject;
import javax.inject.Singleton;
/**
* Holds registered event listeners. Will contain nothing if tracking disabled. Service registered
* in guice and may be injected directly (e.g. for unit tests).
*
* @author Vyacheslav Rusakov
* @since 12.10.2016
*/
@SuppressWarnings({"rawtypes", "UnstableApiUsage"})
@Singleton
public class EventSubscribersInfo {
private final SubscriptionIntrospector introspect;
@Inject
public EventSubscribersInfo(final EventBus eventbus) {
this.introspect = new SubscriptionIntrospector(eventbus);
}
/**
* May return not just event types, because method could listen for events abstract type or {@link
* Object} to receive all events.
*
* @return set of events with known subscribers or empty set
*/
public Set getListenedEvents() {
return introspect.getListenedEvents();
}
/**
* NOTE: method may return not all listeners, because some methods may listen for a range of
* events (by base class or {@link Object}). Only direct subscriptions are tracked.
*
* @param event event class to get listeners for
* @return collection of classes listening for event type, or empty list
*/
public Set getListenerTypes(final Class event) {
return introspect.getSubscriberTypes(event);
}
/**
* NOTE: method may return not all listeners, because some methods may listen for a range of
* events (by base class or {@link Object}). Only direct subscriptions are tracked.
*
* @param event event class to get listeners for
* @return collection of instances listening for event type, or empty list
*/
public Set