01: /*
02: * Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
03: *
04: * This file is part of Resin(R) Open Source
05: *
06: * Each copy or derived work must preserve the copyright notice and this
07: * notice unmodified.
08: *
09: * Resin Open Source is free software; you can redistribute it and/or modify
10: * it under the terms of the GNU General Public License as published by
11: * the Free Software Foundation; either version 2 of the License, or
12: * (at your option) any later version.
13: *
14: * Resin Open Source is distributed in the hope that it will be useful,
15: * but WITHOUT ANY WARRANTY; without even the implied warranty of
16: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17: * of NON-INFRINGEMENT. See the GNU General Public License for more
18: * details.
19: *
20: * You should have received a copy of the GNU General Public License
21: * along with Resin Open Source; if not, write to the
22: *
23: * Free Software Foundation, Inc.
24: * 59 Temple Place, Suite 330
25: * Boston, MA 02111-1307 USA
26: *
27: * @author Scott Ferguson
28: */
29:
30: package com.caucho.db.store;
31:
32: import com.caucho.log.Log;
33: import com.caucho.util.L10N;
34:
35: import java.util.logging.Logger;
36:
37: /**
38: * Represents a versioned row
39: */
40: public class ReadBlock extends Block {
41: private static final Logger log = Log.open(ReadBlock.class);
42: private static final L10N L = new L10N(ReadBlock.class);
43:
44: private byte[] _buffer;
45:
46: ReadBlock(Store store, long blockId) {
47: super (store, blockId);
48:
49: _buffer = _freeBuffers.allocate();
50: if (_buffer == null)
51: _buffer = new byte[Store.BLOCK_SIZE];
52: }
53:
54: /**
55: * Returns the block's buffer.
56: */
57: public byte[] getBuffer() {
58: return _buffer;
59: }
60:
61: /**
62: * Called when the block is removed from the cache.
63: */
64: protected void freeImpl() {
65: //System.out.println(this + " FREE-IMPL");
66: synchronized (this ) {
67: byte[] buffer = _buffer;
68: _buffer = null;
69:
70: if (buffer != null)
71: _freeBuffers.free(buffer);
72: }
73: }
74:
75: public String toString() {
76: return "ReadBlock[" + getStore() + "," + getBlockId()
77: / Store.BLOCK_SIZE + "]";
78: }
79: }
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