| /* |
| * Copyright 2015-present Open Networking Laboratory |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.onosproject.net.provider; |
| |
| import org.apache.felix.scr.annotations.Component; |
| import org.apache.felix.scr.annotations.Reference; |
| import org.apache.felix.scr.annotations.ReferenceCardinality; |
| import org.onosproject.event.Event; |
| import org.onosproject.event.EventDeliveryService; |
| import org.onosproject.event.EventListener; |
| import org.onosproject.event.ListenerRegistry; |
| import org.onosproject.event.ListenerService; |
| |
| /** |
| * Basis for components which need to export listener mechanism. |
| */ |
| @Component(componentAbstract = true) |
| public abstract class AbstractListenerProviderRegistry<E extends Event, L extends EventListener<E>, |
| P extends Provider, S extends ProviderService<P>> |
| extends AbstractProviderRegistry<P, S> implements ListenerService<E, L> { |
| |
| // If only Java supported mixins... |
| |
| protected final ListenerRegistry<E, L> listenerRegistry = new ListenerRegistry<>(); |
| |
| @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) |
| protected EventDeliveryService eventDispatcher; |
| |
| @Override |
| public void addListener(L listener) { |
| listenerRegistry.addListener(listener); |
| } |
| |
| @Override |
| public void removeListener(L listener) { |
| listenerRegistry.removeListener(listener); |
| } |
| |
| |
| /** |
| * Safely posts the specified event to the local event dispatcher. |
| * If there is no event dispatcher or if the event is null, this method |
| * is a noop. |
| * |
| * @param event event to be posted; may be null |
| */ |
| protected void post(E event) { |
| if (event != null && eventDispatcher != null) { |
| eventDispatcher.post(event); |
| } |
| } |
| |
| } |