| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.pulsar.broker.service; |
| |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.Objects; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.CopyOnWriteArrayList; |
| import lombok.extern.slf4j.Slf4j; |
| |
| /** |
| * Utility class to dispatch topic events. |
| */ |
| @Slf4j |
| public class TopicEventsDispatcher { |
| private final List<TopicEventsListener> topicEventListeners = new CopyOnWriteArrayList<>(); |
| |
| /** |
| * Adds listeners, ignores null listeners. |
| * @param listeners |
| */ |
| public void addTopicEventListener(TopicEventsListener... listeners) { |
| Objects.requireNonNull(listeners); |
| Arrays.stream(listeners) |
| .filter(x -> x != null) |
| .forEach(topicEventListeners::add); |
| } |
| |
| /** |
| * Removes listeners. |
| * @param listeners |
| */ |
| public void removeTopicEventListener(TopicEventsListener... listeners) { |
| Objects.requireNonNull(listeners); |
| Arrays.stream(listeners) |
| .filter(x -> x != null) |
| .forEach(topicEventListeners::remove); |
| } |
| |
| /** |
| * Dispatches notification to all currently added listeners. |
| * @param topic |
| * @param event |
| * @param stage |
| */ |
| public void notify(String topic, |
| TopicEventsListener.TopicEvent event, |
| TopicEventsListener.EventStage stage) { |
| notify(topic, event, stage, null); |
| } |
| |
| /** |
| * Dispatches notification to all currently added listeners. |
| * @param topic |
| * @param event |
| * @param stage |
| * @param t |
| */ |
| public void notify(String topic, |
| TopicEventsListener.TopicEvent event, |
| TopicEventsListener.EventStage stage, |
| Throwable t) { |
| topicEventListeners |
| .forEach(listener -> notify(listener, topic, event, stage, t)); |
| } |
| |
| /** |
| * Dispatches SUCCESS/FAILURE notification to all currently added listeners on completion of the future. |
| * @param future |
| * @param topic |
| * @param event |
| * @param <T> |
| * @return future of a new completion stage |
| */ |
| public <T> CompletableFuture<T> notifyOnCompletion(CompletableFuture<T> future, |
| String topic, |
| TopicEventsListener.TopicEvent event) { |
| return future.whenComplete((r, ex) -> notify(topic, |
| event, |
| ex == null ? TopicEventsListener.EventStage.SUCCESS : TopicEventsListener.EventStage.FAILURE, |
| ex)); |
| } |
| |
| /** |
| * Dispatches notification to specified listeners. |
| * @param listeners |
| * @param topic |
| * @param event |
| * @param stage |
| * @param t |
| */ |
| public static void notify(TopicEventsListener[] listeners, |
| String topic, |
| TopicEventsListener.TopicEvent event, |
| TopicEventsListener.EventStage stage, |
| Throwable t) { |
| Objects.requireNonNull(listeners); |
| for (TopicEventsListener listener: listeners) { |
| notify(listener, topic, event, stage, t); |
| } |
| } |
| |
| private static void notify(TopicEventsListener listener, |
| String topic, |
| TopicEventsListener.TopicEvent event, |
| TopicEventsListener.EventStage stage, |
| Throwable t) { |
| if (listener == null) { |
| return; |
| } |
| |
| try { |
| listener.handleEvent(topic, event, stage, t); |
| } catch (Throwable ex) { |
| log.error("TopicEventsListener {} exception while handling {}_{} for topic {}", |
| listener, event, stage, topic, ex); |
| } |
| } |
| |
| } |