01: /* Copyright (C) 2004 - 2007 db4objects Inc. http://www.db4o.com
02:
03: This file is part of the db4o open source object database.
04:
05: db4o is free software; you can redistribute it and/or modify it under
06: the terms of version 2 of the GNU General Public License as published
07: by the Free Software Foundation and as clarified by db4objects' GPL
08: interpretation policy, available at
09: http://www.db4o.com/about/company/legalpolicies/gplinterpretation/
10: Alternatively you can write to db4objects, Inc., 1900 S Norfolk Street,
11: Suite 350, San Mateo, CA 94403, USA.
12:
13: db4o is distributed in the hope that it will be useful, but WITHOUT ANY
14: WARRANTY; without even the implied warranty of MERCHANTABILITY or
15: FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16: for more details.
17:
18: You should have received a copy of the GNU General Public License along
19: with this program; if not, write to the Free Software Foundation, Inc.,
20: 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
21: package com.db4o.internal;
22:
23: import com.db4o.ext.*;
24: import com.db4o.internal.handlers.*;
25: import com.db4o.internal.marshall.*;
26: import com.db4o.internal.slots.*;
27: import com.db4o.marshall.*;
28:
29: /**
30: * @exclude
31: */
32: public class VersionFieldMetadata extends VirtualFieldMetadata {
33:
34: VersionFieldMetadata(ObjectContainerBase stream) {
35: super (Handlers4.LONG_ID, new LongHandler(stream));
36: setName(VirtualField.VERSION);
37: }
38:
39: public void addFieldIndex(MarshallerFamily mf,
40: ClassMetadata yapClass, StatefulBuffer writer, Slot oldSlot) {
41: writer.writeLong(writer.getStream().generateTimeStampId());
42: }
43:
44: public void delete(MarshallerFamily mf, StatefulBuffer a_bytes,
45: boolean isUpdate) {
46: a_bytes.incrementOffset(linkLength());
47: }
48:
49: void instantiate1(Transaction a_trans, ObjectReference a_yapObject,
50: Buffer a_bytes) {
51: a_yapObject.virtualAttributes().i_version = a_bytes.readLong();
52: }
53:
54: void marshall(Transaction trans, ObjectReference ref,
55: WriteBuffer buffer, boolean isMigrating, boolean isNew) {
56: VirtualAttributes attr = ref.virtualAttributes();
57: if (!isMigrating) {
58: attr.i_version = trans.container()._parent
59: .generateTimeStampId();
60: }
61: if (attr == null) {
62: buffer.writeLong(0);
63: } else {
64: buffer.writeLong(attr.i_version);
65: }
66: }
67:
68: protected int linkLength() {
69: return Const4.LONG_LENGTH;
70: }
71:
72: void marshallIgnore(WriteBuffer buffer) {
73: buffer.writeLong(0);
74: }
75:
76: }
|