001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.activemq.broker.region.policy;
018    
019    import org.apache.activemq.broker.region.Subscription;
020    import org.apache.activemq.command.ActiveMQDestination;
021    import org.apache.activemq.command.Message;
022    
023    /**
024     * A strategy for choosing which destination is used for dead letter queue messages.
025     *
026     *
027     */
028    public interface DeadLetterStrategy {
029    
030        /**
031         * Allow pluggable strategy for deciding if message should be sent to a dead letter queue
032         * for example, you might not want to ignore expired or non-persistent messages
033         * @param message
034         * @return true if message should be sent to a dead letter queue
035         */
036        boolean isSendToDeadLetterQueue(Message message);
037    
038        /**
039         * Returns the dead letter queue for the given message and subscription.
040         */
041        ActiveMQDestination getDeadLetterQueueFor(Message message, Subscription subscription);
042    
043        /**
044         * @return true if processes expired messages
045         */
046        public boolean isProcessExpired() ;
047    
048        /**
049         * @param processExpired the processExpired to set
050         */
051        public void setProcessExpired(boolean processExpired);
052    
053        /**
054         * @return the processNonPersistent
055         */
056        public boolean isProcessNonPersistent();
057    
058        /**
059         * @param processNonPersistent the processNonPersistent to set
060         */
061        public void setProcessNonPersistent(boolean processNonPersistent);
062    
063        public boolean isDLQ(ActiveMQDestination destination);
064    
065        /**
066         * Allows for a Message that was already processed by a DLQ to be rolled back in case
067         * of a move or a retry of that message, otherwise the Message would be considered a
068         * duplicate if this strategy is doing Message Auditing.
069         *
070         * @param message
071         */
072        public void rollback(Message message);
073    
074    }