KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > db4o > inside > classindex > AbstractClassIndexStrategy


1 /* Copyright (C) 2004 - 2006 db4objects Inc. http://www.db4o.com
2
3 This file is part of the db4o open source object database.
4
5 db4o is free software; you can redistribute it and/or modify it under
6 the terms of version 2 of the GNU General Public License as published
7 by the Free Software Foundation and as clarified by db4objects' GPL
8 interpretation policy, available at
9 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.inside.classindex;
22
23 import com.db4o.*;
24
25 /**
26  * @exclude
27  */

28 public abstract class AbstractClassIndexStrategy implements ClassIndexStrategy {
29
30     protected final YapClass _yapClass;
31
32     public AbstractClassIndexStrategy(YapClass yapClass) {
33         _yapClass = yapClass;
34     }
35
36     protected int yapClassID() {
37         return _yapClass.getID();
38     }
39
40     public int ownLength() {
41         return YapConst.ID_LENGTH;
42     }
43
44     protected abstract void internalAdd(Transaction trans, int id);
45
46     public final void add(Transaction trans, int id) {
47         if (DTrace.enabled) {
48             DTrace.ADD_TO_CLASS_INDEX.log(id);
49         }
50         checkId(id);
51         internalAdd(trans, id);
52     }
53
54     protected abstract void internalRemove(Transaction ta, int id);
55
56     public final void remove(Transaction ta, int id) {
57         if (DTrace.enabled){
58             DTrace.REMOVE_FROM_CLASS_INDEX.log(id);
59         }
60         checkId(id);
61         internalRemove(ta, id);
62     }
63     
64     private void checkId(int id) {
65         if (Deploy.debug) {
66             if (id == 0) {
67                 throw new IllegalArgumentException JavaDoc("id can't be zero");
68             }
69         }
70     }
71 }
Popular Tags