| /* |
| * |
| * 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.qpid.protocol; |
| |
| import org.apache.qpid.AMQException; |
| import org.apache.qpid.framing.AMQMethodBody; |
| |
| /** |
| * AMQMethodListener is a listener that receives notifications of AMQP methods. The methods are packaged as events in |
| * {@link AMQMethodEvent}. |
| * |
| * <p/>An event listener may be associated with a particular context, usually an AMQP channel, and in addition to |
| * receiving method events will be notified of errors on that context. This enables listeners to perform any clean |
| * up that they need to do before the context is closed or retried. |
| * |
| * <p/><table id="crc"><caption>CRC Card</caption> |
| * <tr><th> Responsibilities |
| * <tr><td> Accept notification of AMQP method events. <td> {@link AMQMethodEvent} |
| * <tr><td> Accept notification of errors on the event context. |
| * </table> |
| * |
| * @todo Document why the exception is passed to the error method. Is it so that the exception can be passed |
| * from the event handling thread to another thread and rethown from there? It is unusual to pass exceptions as |
| * method arguments, because they have their own mechanism for propagating through the call stack, so some |
| * explanation ought to be provided. |
| */ |
| public interface AMQMethodListener |
| { |
| /** |
| * Notifies the listener that an AMQP method event has occurred. |
| * |
| * @param evt The AMQP method event (contains the method and channel). |
| * |
| * @return <tt>true</tt> if the handler processes the method frame, <tt>false<tt> otherwise. Note that this does |
| * not prohibit the method event being delivered to subsequent listeners but can be used to determine if |
| * nobody has dealt with an incoming method frame. |
| * |
| * @throws Exception if an error has occurred. This exception may be delivered to all registered listeners using |
| * the error() method (see below) allowing them to perform cleanup if necessary. |
| * |
| * @todo Consider narrowing the exception. |
| */ |
| <B extends AMQMethodBody> boolean methodReceived(AMQMethodEvent<B> evt) throws AMQException; |
| |
| /** |
| * Notifies the listener of an error on the event context to which it is listening. The listener should perform |
| * any necessary clean-up for the context. |
| * |
| * @param e The underlying exception that is the source of the error. |
| */ |
| void error(Exception e); |
| } |