CommunicationManager.java

package ch.unifr.pai.twice.comm.serverPush.client;

/*
 * Copyright 2013 Oliver Schmid
 * 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.
 */

import com.google.gwt.core.client.GWT;
import com.google.web.bindery.event.shared.EventBus;

/**
 * A central class to access the different functionalities of messaging
 * 
 * @author Oliver Schmid
 * 
 */
public class CommunicationManager {
	//
	// private static EventBus unidirectionalEventBus;
	private static EventBus bidirectionalEventBus;

	// public static void sendDirectMessageToDevice(String receipientUuid, String message){
	// getUnidirectionalEventBus().
	//
	// }

	// /**
	// * @param event
	// */
	// public void sendEvent(RemoteEvent<?> event) {
	// bidirectionalEventBus.fireEvent(event);
	// }

	/**
	 * At the moment, we do not have the unidirectional event bus ready, therefore we return a bidirectional event bus.
	 * 
	 * Should be: Gives the unidirectional event bus of an application. Be aware that only {@link DiscardingRemoteEvent}s can be sent through this event bus
	 * since the client is not notified if there are any conflicts
	 * 
	 * @return a unidirectional event bus unless a bidirectional already exists.
	 */
	public static EventBus getUnidirectionalEventBus() {
		// //If a bidirectional event bus already exists, use that one
		// if(bidirectionalEventBus!=null){
		// return bidirectionalEventBus;
		// }
		// else if(unidirectionalEventBus==null){
		// //Lazy initialization of the unidiresendMessagectional event bus
		// unidirectionalEventBus = GWT.create(UnidirectionalEventBus.class);
		// }
		// return unidirectionalEventBus;
		return getBidirectionalEventBus();
	}

	/**
	 * @return the bidirectional event bus. The underlying logic negotiates the best communication pattern by itself. Since the bidirectional event bus is a
	 *         singleton, multiple calls to this method will always return the same instance.
	 */
	public static EventBus getBidirectionalEventBus() {
		if (bidirectionalEventBus == null) {
			// Lazy initialization of the bidirectional event bus
			bidirectionalEventBus = GWT.create(ServerPushEventBus.class);
		}
		return bidirectionalEventBus;
	}
}