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 */
017package org.apache.activemq.broker.region;
018
019import org.apache.activemq.command.ConsumerId;
020import org.apache.activemq.command.Message;
021import org.apache.activemq.command.MessageId;
022
023/**
024 * Keeps track of a message that is flowing through the Broker.  This 
025 * object may hold a hard reference to the message or only hold the
026 * id of the message if the message has been persisted on in a MessageStore.
027 * 
028 * 
029 */
030public interface MessageReference {
031    
032    MessageId getMessageId();
033    Message getMessageHardRef();
034    Message getMessage();
035    boolean isPersistent();
036    
037    Message.MessageDestination getRegionDestination();
038    
039    int getRedeliveryCounter();
040    void incrementRedeliveryCounter();
041    
042    int getReferenceCount();
043    
044    int incrementReferenceCount();
045    int decrementReferenceCount();
046    ConsumerId getTargetConsumerId();
047    int getSize();
048    long getExpiration();
049    String getGroupID();
050    int getGroupSequence();
051    
052    /**
053     * Returns true if this message is expired
054     */
055    boolean isExpired();
056
057    /**
058     * Returns true if this message is dropped.
059     */
060    boolean isDropped();
061    
062    /**
063     * @return true if the message is an advisory
064     */
065    boolean isAdvisory();
066
067    boolean canProcessAsExpired();
068    
069}