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1   /*** 
2    * 
3    * Copyright 2004 Protique Ltd
4    * 
5    * Licensed under the Apache License, Version 2.0 (the "License"); 
6    * you may not use this file except in compliance with the License. 
7    * You may obtain a copy of the License at 
8    * 
9    * http://www.apache.org/licenses/LICENSE-2.0
10   * 
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS, 
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
14   * See the License for the specific language governing permissions and 
15   * limitations under the License. 
16   * 
17   **/
18  package org.codehaus.activemq.store.jdbm;
19  
20  import jdbm.RecordManager;
21  import jdbm.RecordManagerFactory;
22  import jdbm.btree.BTree;
23  import org.apache.commons.logging.Log;
24  import org.apache.commons.logging.LogFactory;
25  import org.codehaus.activemq.AlreadyClosedException;
26  import org.codehaus.activemq.service.impl.PersistenceAdapterSupport;
27  import org.codehaus.activemq.store.MessageStore;
28  import org.codehaus.activemq.store.PreparedTransactionStore;
29  import org.codehaus.activemq.store.TopicMessageStore;
30  import org.codehaus.activemq.util.DefaultComparator;
31  import org.codehaus.activemq.util.JMSExceptionHelper;
32  
33  import javax.jms.JMSException;
34  import java.io.File;
35  import java.io.IOException;
36  import java.util.Comparator;
37  import java.util.Properties;
38  
39  /***
40   * A {@link org.codehaus.activemq.store.PersistenceAdapter} implementation for
41   * <a href="http://jdbm.sf.net/">JDBM</a>
42   *
43   * @version $Revision: 1.5 $
44   */
45  public class JdbmPersistenceAdapter extends PersistenceAdapterSupport {
46  
47      private static final Log log = LogFactory.getLog(JdbmPersistenceAdapter.class);
48  
49      private RecordManager manager;
50      private File directory = new File("ActiveMQ");
51      private Properties properties;
52  
53      /***
54       * Factory method to create an instance using the defaults
55       *
56       * @param directory the directory in which to store the persistent files
57       * @return
58       * @throws JMSException
59       */
60      public static JdbmPersistenceAdapter newInstance(File directory) throws JMSException {
61          return new JdbmPersistenceAdapter(directory);
62      }
63  
64  
65      public JdbmPersistenceAdapter() {
66      }
67  
68      public JdbmPersistenceAdapter(File directory) {
69          this.directory = directory;
70      }
71  
72      public JdbmPersistenceAdapter(RecordManager manager) {
73          this.manager = manager;
74      }
75  
76      public MessageStore createQueueMessageStore(String destinationName) throws JMSException {
77          try {
78              BTree messageDb = createDatabase("Queue_" + destinationName);
79              BTree sequenceDb = createDatabase("Sequence_Queue_" + destinationName);
80              JdbmMessageStore messageStore = new JdbmMessageStore(messageDb, sequenceDb);
81              return messageStore;
82          }
83          catch (IOException e) {
84              throw JMSExceptionHelper.newJMSException("Failed to create a QueueMessageContainer for destination: " + destinationName + ". Reason: " + e, e);
85          }
86      }
87  
88      public TopicMessageStore createTopicMessageStore(String destinationName) throws JMSException {
89          try {
90              BTree messageDb = createDatabase("Topic_" + destinationName);
91              BTree sequenceDb = createDatabase("Sequence_Topic_" + destinationName);
92              BTree consumerAckDb = createDatabase("Consumer_Acks_Topic_" + destinationName);
93              BTree subscriberDb = createDatabase("Subscriber_" + destinationName);
94              BTree messageCountDb = createDatabase("MessageCount_Topic_" + destinationName);
95              JdbmTopicMessageStore messageStore = new JdbmTopicMessageStore(messageDb, sequenceDb, consumerAckDb, subscriberDb, messageCountDb);
96              return messageStore;
97          }
98          catch (IOException e) {
99              throw JMSExceptionHelper.newJMSException("Failed to create a TopicMessageContainer for destination: " + destinationName + ". Reason: " + e, e);
100         }
101     }
102 
103     public PreparedTransactionStore createPreparedTransactionStore() throws JMSException {
104         try {
105             return new JdbmPreparedTransactionStore(createDatabase("XaPrepareTxnDb"));
106         }
107         catch (IOException e) {
108             throw JMSExceptionHelper.newJMSException("Could not create XA Prepare Transaction Database. Reason: " + e, e);
109         }
110     }
111 
112     public void beginTransaction() {
113     }
114 
115     public void commitTransaction() throws JMSException {
116         try {
117             manager.commit();
118         }
119         catch (IOException e) {
120             throw JMSExceptionHelper.newJMSException("Could not commit transaction. Reason: " + e, e);
121         }
122     }
123 
124     public void rollbackTransaction() {
125         try {
126             manager.rollback();
127         }
128         catch (IOException e) {
129             log.error("Could not rollback transaction. Reason: " + e, e);
130         }
131     }
132 
133     public void start() throws JMSException {
134         if (manager == null) {
135             directory.mkdirs();
136 
137             log.info("Creating JDBM based message store in directory: " + directory.getAbsolutePath());
138 
139             try {
140                 String name = directory.getAbsolutePath() + "/Store";
141                 if (properties != null) {
142                     manager = RecordManagerFactory.createRecordManager(name, properties);
143                 }
144                 else {
145                     manager = RecordManagerFactory.createRecordManager(name);
146                 }
147             }
148             catch (IOException e) {
149                 throw JMSExceptionHelper.newJMSException("Failed to create JDBM persistent store at directory: "
150                         + directory + ". Reason: " + e, e);
151             }
152         }
153     }
154 
155     public synchronized void stop() throws JMSException {
156         if (manager != null) {
157             try {
158                 manager.close();
159             }
160             catch (IOException e) {
161                 throw JMSExceptionHelper.newJMSException("Failed to close PersistenceAdapter. Reason: " + e, e);
162             }
163             finally {
164                 manager = null;
165             }
166         }
167     }
168 
169     // Properties
170     //-------------------------------------------------------------------------
171     public RecordManager getManager() {
172         return manager;
173     }
174 
175     public void setManager(RecordManager manager) {
176         this.manager = manager;
177     }
178 
179     public File getDirectory() {
180         return directory;
181     }
182 
183     public void setDirectory(File directory) {
184         this.directory = directory;
185     }
186 
187     // Implementation methods
188     //-------------------------------------------------------------------------
189     public synchronized BTree createDatabase(String name) throws IOException, AlreadyClosedException {
190         if (manager == null) {
191             throw new AlreadyClosedException("JDBM PersistenceAdapter");
192         }
193 
194         // try to reload an existing B+Tree
195         long recid = manager.getNamedObject(name);
196         BTree tree = null;
197         if (recid != 0) {
198             tree = BTree.load(manager, recid);
199         }
200         else {
201             Comparator comparator = new DefaultComparator();
202             //Comparator comparator = new ObjectBAComparator(new DefaultComparator());
203             tree = BTree.createInstance(manager, comparator);
204             manager.setNamedObject(name, tree.getRecid());
205         }
206         return tree;
207     }
208 
209 }