1 | /* ============================================================= |
2 | * SmallSQL : a free Java DBMS library for the Java(tm) platform |
3 | * ============================================================= |
4 | * |
5 | * (C) Copyright 2004-2006, by Volker Berlin. |
6 | * |
7 | * Project Info: http://www.smallsql.de/ |
8 | * |
9 | * This library is free software; you can redistribute it and/or modify it |
10 | * under the terms of the GNU Lesser General Public License as published by |
11 | * the Free Software Foundation; either version 2.1 of the License, or |
12 | * (at your option) any later version. |
13 | * |
14 | * This library is distributed in the hope that it will be useful, but |
15 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
16 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
17 | * License for more details. |
18 | * |
19 | * You should have received a copy of the GNU Lesser General Public |
20 | * License along with this library; if not, write to the Free Software |
21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
22 | * USA. |
23 | * |
24 | * [Java is a trademark or registered trademark of Sun Microsystems, Inc. |
25 | * in the United States and other countries.] |
26 | * |
27 | * --------------- |
28 | * StorePage.java |
29 | * --------------- |
30 | * Author: Volker Berlin |
31 | * |
32 | * Created on 28.08.2004 |
33 | */ |
34 | package smallsql.database; |
35 | |
36 | import java.io.*; |
37 | import java.sql.SQLException; |
38 | |
39 | /** |
40 | * @author Volker Berlin |
41 | */ |
42 | class StorePage { |
43 | byte[] page; // Daten einer Page |
44 | int pageSize; |
45 | RandomAccessFile raFile; |
46 | long fileOffset; // Position in Datei |
47 | |
48 | StorePage(byte[] page, int pageSize, RandomAccessFile raFile, long fileOffset){ |
49 | this.page = page; |
50 | this.pageSize = pageSize; |
51 | this.raFile = raFile; |
52 | this.fileOffset = fileOffset; |
53 | } |
54 | |
55 | |
56 | final void setPageData(byte[] data, int size){ |
57 | page = data; |
58 | pageSize = size; |
59 | } |
60 | |
61 | |
62 | long commit() throws SQLException{ |
63 | try{ |
64 | if(raFile != null){ |
65 | // if new page then append at end of file |
66 | if(fileOffset < 0){ |
67 | fileOffset = raFile.length(); |
68 | } |
69 | raFile.seek(fileOffset); |
70 | raFile.write(page, 0, pageSize); |
71 | //raFile.getFD().sync(); |
72 | } |
73 | return fileOffset; |
74 | }catch(Exception e){ |
75 | throw Utils.createSQLException(e); |
76 | } |
77 | } |
78 | |
79 | |
80 | final void rollback(){ |
81 | raFile = null; |
82 | } |
83 | |
84 | void freeLock(){} |
85 | } |