/*
* 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.jclouds.events.config;
import static com.google.inject.Scopes.SINGLETON;
import static org.jclouds.Constants.PROPERTY_USER_THREADS;
import javax.inject.Named;
import javax.inject.Singleton;
import org.jclouds.concurrent.config.ExecutorServiceModule;
import org.jclouds.events.config.annotations.AsyncBus;
import org.jclouds.events.handlers.DeadEventLoggingHandler;
import com.google.common.eventbus.AsyncEventBus;
import com.google.common.eventbus.EventBus;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.inject.AbstractModule;
import com.google.inject.Provides;
/**
* Configures the {@link EventBus} to be used in the platform.
* <p>
* This class will provide an {@link AsyncEventBus} to be used to provide a basic pub/sub system for asynchronous
* operations.
*
* @author Ignasi Barrera
*
* @see ExecutorServiceModule
* @see AsyncEventBus
* @see EventBus
* @see AsyncBus
*/
@ConfiguresEventBus
public class EventBusModule extends AbstractModule {
/**
* Provides an {@link AsyncEventBus} that will use the configured executor service to dispatch events to subscribers.
*/
@Provides
@Singleton
AsyncEventBus provideAsyncEventBus(@Named(PROPERTY_USER_THREADS) ListeningExecutorService userExecutor,
DeadEventLoggingHandler deadEventsHandler) {// NO_UCD
AsyncEventBus asyncBus = new AsyncEventBus("jclouds-async-event-bus", userExecutor);
asyncBus.register(deadEventsHandler);
return asyncBus;
}
/**
* Provides asynchronous {@link EventBus}.
*/
@Provides
@Singleton
EventBus provideSyncEventBus(DeadEventLoggingHandler deadEventsHandler) { // NO_UCD
EventBus syncBus = new EventBus("jclouds-sync-event-bus");
syncBus.register(deadEventsHandler);
return syncBus;
}
/**
* Configures the {@link EventBus} to be singleton and enables the {@link AsyncBus} annotation.
*/
@Override
protected void configure() {
bind(EventBus.class).annotatedWith(AsyncBus.class).to(AsyncEventBus.class).in(SINGLETON);
}
}