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1   /*   Open Source Java Caching Service
2   *    Copyright (C) 2002 Frank Karlstrøm
3   *    This library is free software; you can redistribute it and/or
4   *    modify it under the terms of the GNU Lesser General Public
5   *    License as published by the Free Software Foundation; either
6   *    version 2.1 of the License, or (at your option) any later version.
7   *
8   *    This library is distributed in the hope that it will be useful,
9   *    but WITHOUT ANY WARRANTY; without even the implied warranty of
10  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11  *    Lesser General Public License for more details.
12  *
13  *    You should have received a copy of the GNU Lesser General Public
14  *    License along with this library; if not, write to the Free Software
15  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
16  *
17  *    The author can be contacted by email: fjankk@users.sourceforge.net
18  */
19  package org.fjank.jcache.persistence;
20  
21  import java.io.Serializable;
22  
23  
24  /**
25   * Disk objects are located by descriptor entries. These are saved on shutdown
26   * and loaded into memory on startup.
27   */
28  class DiskElementDescriptor implements Serializable {
29      /** the position where the object starts */
30      long pos;
31  
32      /** the length of the object */
33      int len;
34  
35      /**
36       * Creates a new DiskElementDescriptor object.
37       */
38      DiskElementDescriptor() {
39      }
40  
41      /**
42       * initializes this descriptor with the position to start at, and a byte[]
43       * with the actual data which is to be written.
44       *
45       * @param pos2 the starting position
46       * @param data the data to write.
47       */
48      void init(final long pos2, final byte[] data) {
49          this.pos = pos2;
50          this.len = data.length;
51      }
52  }