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.store.memory; 018 019 import java.io.IOException; 020 import java.util.Collections; 021 import java.util.Iterator; 022 import java.util.LinkedHashMap; 023 import java.util.Map; 024 import java.util.Map.Entry; 025 026 import org.apache.activemq.broker.ConnectionContext; 027 import org.apache.activemq.command.ActiveMQDestination; 028 import org.apache.activemq.command.Message; 029 import org.apache.activemq.command.MessageAck; 030 import org.apache.activemq.command.MessageId; 031 import org.apache.activemq.store.MessageRecoveryListener; 032 import org.apache.activemq.store.MessageStore; 033 import org.apache.activemq.store.AbstractMessageStore; 034 import org.apache.activemq.usage.MemoryUsage; 035 import org.apache.activemq.usage.SystemUsage; 036 037 /** 038 * An implementation of {@link org.apache.activemq.store.MessageStore} which 039 * uses a 040 * 041 * @version $Revision: 1.7 $ 042 */ 043 public class MemoryMessageStore extends AbstractMessageStore { 044 045 protected final Map<MessageId, Message> messageTable; 046 protected MessageId lastBatchId; 047 048 public MemoryMessageStore(ActiveMQDestination destination) { 049 this(destination, new LinkedHashMap<MessageId, Message>()); 050 } 051 052 public MemoryMessageStore(ActiveMQDestination destination, Map<MessageId, Message> messageTable) { 053 super(destination); 054 this.messageTable = Collections.synchronizedMap(messageTable); 055 } 056 057 public synchronized void addMessage(ConnectionContext context, Message message) throws IOException { 058 synchronized (messageTable) { 059 messageTable.put(message.getMessageId(), message); 060 } 061 message.incrementReferenceCount(); 062 } 063 064 // public void addMessageReference(ConnectionContext context,MessageId 065 // messageId,long expirationTime,String messageRef) 066 // throws IOException{ 067 // synchronized(messageTable){ 068 // messageTable.put(messageId,messageRef); 069 // } 070 // } 071 072 public Message getMessage(MessageId identity) throws IOException { 073 return messageTable.get(identity); 074 } 075 076 // public String getMessageReference(MessageId identity) throws IOException{ 077 // return (String)messageTable.get(identity); 078 // } 079 080 public void removeMessage(ConnectionContext context, MessageAck ack) throws IOException { 081 removeMessage(ack.getLastMessageId()); 082 } 083 084 public void removeMessage(MessageId msgId) throws IOException { 085 synchronized (messageTable) { 086 Message removed = messageTable.remove(msgId); 087 if( removed !=null ) { 088 removed.decrementReferenceCount(); 089 } 090 if ((lastBatchId != null && lastBatchId.equals(msgId)) || messageTable.isEmpty()) { 091 lastBatchId = null; 092 } 093 } 094 } 095 096 public void recover(MessageRecoveryListener listener) throws Exception { 097 // the message table is a synchronizedMap - so just have to synchronize 098 // here 099 synchronized (messageTable) { 100 for (Iterator<Message> iter = messageTable.values().iterator(); iter.hasNext();) { 101 Object msg = iter.next(); 102 if (msg.getClass() == MessageId.class) { 103 listener.recoverMessageReference((MessageId)msg); 104 } else { 105 listener.recoverMessage((Message)msg); 106 } 107 } 108 } 109 } 110 111 public void removeAllMessages(ConnectionContext context) throws IOException { 112 synchronized (messageTable) { 113 messageTable.clear(); 114 } 115 } 116 117 public void delete() { 118 synchronized (messageTable) { 119 messageTable.clear(); 120 } 121 } 122 123 124 public int getMessageCount() { 125 return messageTable.size(); 126 } 127 128 public void recoverNextMessages(int maxReturned, MessageRecoveryListener listener) throws Exception { 129 synchronized (messageTable) { 130 boolean pastLackBatch = lastBatchId == null; 131 int count = 0; 132 for (Iterator iter = messageTable.entrySet().iterator(); iter.hasNext();) { 133 Map.Entry entry = (Entry)iter.next(); 134 if (pastLackBatch) { 135 count++; 136 Object msg = entry.getValue(); 137 lastBatchId = (MessageId)entry.getKey(); 138 if (msg.getClass() == MessageId.class) { 139 listener.recoverMessageReference((MessageId)msg); 140 } else { 141 listener.recoverMessage((Message)msg); 142 } 143 } else { 144 pastLackBatch = entry.getKey().equals(lastBatchId); 145 } 146 } 147 } 148 } 149 150 public void resetBatching() { 151 lastBatchId = null; 152 } 153 154 @Override 155 public void setBatch(MessageId messageId) { 156 lastBatchId = messageId; 157 } 158 159 }