dojox.cometd.MessageListener Maven / Gradle / Ivy
// ========================================================================
// Copyright 2007 Dojo Foundation
// ------------------------------------------------------------------------
// 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 dojox.cometd;
import java.util.EventListener;
/**
* Message Listener Interface.
*
* Objects implementing this interface may listen for message deliverly events
* by calling the {@link Client#addListener(EventListener)}. The {@link Synchronous}
* or {@link Asynchronous} nested interfaces may be used as a mixin to specify the style
* of delivery required. If neither subtype is specified, then the {@link Bayeux}
* implementation may use either method.
*
* @author gregw
*
*/
public interface MessageListener extends EventListener
{
/**
* Called when a message is delivered to the client
* @param msg TODO
*/
public void deliver(Client fromClient, Client toClient, Message msg);
/**
* Subtype of MessageListener that requires synchronous message delivery.
* The {@link Client} object is locked during the call to
* {@link MessageListener#deliver(Client, Client, Message)}, thus
* guaranteeing that only a single message will be delivered at once and
* in order of receipt.
*
*/
public interface Synchronous {};
/**
* subtype of MesssageListener that requires asynchronous message delivery.
* Calls to {@link MessageListener#deliver(Client, Client, Message)} may occur
* in parallel and possible out of order.
*
*/
public interface Asynchronous {};
}