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1   /*
2    * Copyright 2004 Charles Blaxland
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *     http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package mnemosyne.archiver;
17  
18  import org.apache.commons.logging.Log;
19  import org.apache.commons.logging.LogFactory;
20  
21  import java.io.*;
22  
23  /***
24   * @version $Id: TransactionDirectory.java,v 1.1.1.1 2004/08/07 06:40:54 charlesblaxland Exp $
25   */
26  public class TransactionDirectory extends ArchiveDirectory
27  {
28      private static final Log log = LogFactory.getLog(TransactionDirectory.class);
29  
30      private static final String TRANSACTION_FILE_PREFIX     = "";
31      private static final String TRANSACTION_FILE_POSTFIX    = "_transaction";
32      private static final String TRANSACTION_FILE_EXTENSION  = "txn";
33  
34      public TransactionDirectory(String directoryName, ArchiveSequence sequence)
35      {
36          super(directoryName, sequence);
37      }
38  
39      protected String prefix()
40      {
41          return TRANSACTION_FILE_PREFIX;
42      }
43  
44      protected String postfix()
45      {
46          return TRANSACTION_FILE_POSTFIX;
47      }
48  
49      protected String extension()
50      {
51          return TRANSACTION_FILE_EXTENSION;
52      }
53  
54      public void readTransactionsSinceSnapshot(long snapshotSequenceNumber) throws ArchiverException
55      {
56          if (log.isDebugEnabled())
57              log.debug("Reading all transactions since sequence number " + snapshotSequenceNumber);
58  
59          String firstTransactionFilename = buildArchiveFilename(snapshotSequenceNumber);
60          Object[] filesSinceSnapshot = archiveFiles.tailSet(firstTransactionFilename).toArray();
61  
62          // Read transactions in reverse order
63          for (int i = filesSinceSnapshot.length - 1; i >= 0; i--)
64          {
65              String transactionFilename = (String) filesSinceSnapshot[i];
66              File transactionFile = constructArchiveFile(transactionFilename);
67              readArchiveFile(transactionFile);
68          }
69      }
70  
71  }