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/*
*
* 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.client.failover;
/**
* FailoverException is used to indicate that a synchronous request has failed to receive the reply that it is waiting
* for because the fail-over process has been started whilst it was waiting for its reply. Synchronous methods generally
* raise this exception to indicate that they must be re-tried once the fail-over process has completed.
*
* <p/><table id="crc"><caption>CRC Card</caption>
* <tr><th> Responsibilities <th> Collaborations
* <tr><td> Used to indicate failure of a synchronous request due to fail-over.
* </table>
*
* @todo This exception is created and passed as an argument to a method, rather than thrown. The exception is being
* used to represent an event, passed out to other threads. Use of exceptions as arguments rather than as
* exceptions is extremly confusing. Ideally use a condition or set a flag and check it instead.
* This exceptions-as-events pattern seems to be in a similar style to Mina code, which is not pretty, but
* potentially acceptable for that reason. We have the option of extending the mina model to add more events
* to it, that is, anything that is interested in handling failover as an event occurs below the main
* amq event handler, which knows the specific interface of the qpid handlers, which can pass this down as
* an explicit event, without it being an exception. Add failover method to BlockingMethodFrameListener,
* have it set a flag or interrupt the waiting thread, which then creates and raises this exception.
*/
public class FailoverException extends Exception
{
public FailoverException(String message)
{
super(message);
}
}
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