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.fieldindex;
22:
23: import com.db4o.foundation.Iterator4;
24: import com.db4o.internal.btree.*;
25: import com.db4o.internal.query.processor.*;
26:
27: /**
28: * @exclude
29: */
30: public class IndexedLeaf extends IndexedNodeBase implements
31: IndexedNodeWithRange {
32:
33: private final BTreeRange _range;
34:
35: public IndexedLeaf(QConObject qcon) {
36: super (qcon);
37: _range = search();
38: }
39:
40: private BTreeRange search() {
41: final BTreeRange range = search(constraint().getObject());
42: final QEBitmap bitmap = QEBitmap
43: .forQE(constraint().evaluator());
44: if (bitmap.takeGreater()) {
45: if (bitmap.takeEqual()) {
46: return range.extendToLast();
47: }
48: final BTreeRange greater = range.greater();
49: if (bitmap.takeSmaller()) {
50: return greater.union(range.smaller());
51: }
52: return greater;
53: }
54: if (bitmap.takeSmaller()) {
55: if (bitmap.takeEqual()) {
56: return range.extendToFirst();
57: }
58: return range.smaller();
59: }
60: return range;
61: }
62:
63: public int resultSize() {
64: return _range.size();
65: }
66:
67: public Iterator4 iterator() {
68: return _range.keys();
69: }
70:
71: public BTreeRange getRange() {
72: return _range;
73: }
74: }
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