KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > quadcap > sql > InsertBlob


1 package com.quadcap.sql;
2
3 /* Copyright 1999 - 2003 Quadcap Software. All rights reserved.
4  *
5  * This software is distributed under the Quadcap Free Software License.
6  * This software may be used or modified for any purpose, personal or
7  * commercial. Open Source redistributions are permitted. Commercial
8  * redistribution of larger works derived from, or works which bundle
9  * this software requires a "Commercial Redistribution License"; see
10  * http://www.quadcap.com/purchase.
11  *
12  * Redistributions qualify as "Open Source" under one of the following terms:
13  *
14  * Redistributions are made at no charge beyond the reasonable cost of
15  * materials and delivery.
16  *
17  * Redistributions are accompanied by a copy of the Source Code or by an
18  * irrevocable offer to provide a copy of the Source Code for up to three
19  * years at the cost of materials and delivery. Such redistributions
20  * must allow further use, modification, and redistribution of the Source
21  * Code under substantially the same terms as this license.
22  *
23  * Redistributions of source code must retain the copyright notices as they
24  * appear in each source code file, these license terms, and the
25  * disclaimer/limitation of liability set forth as paragraph 6 below.
26  *
27  * Redistributions in binary form must reproduce this Copyright Notice,
28  * these license terms, and the disclaimer/limitation of liability set
29  * forth as paragraph 6 below, in the documentation and/or other materials
30  * provided with the distribution.
31  *
32  * The Software is provided on an "AS IS" basis. No warranty is
33  * provided that the Software is free of defects, or fit for a
34  * particular purpose.
35  *
36  * Limitation of Liability. Quadcap Software shall not be liable
37  * for any damages suffered by the Licensee or any third party resulting
38  * from use of the Software.
39  */
40
41 import java.io.BufferedOutputStream JavaDoc;
42 import java.io.Externalizable JavaDoc;
43 import java.io.IOException JavaDoc;
44 import java.io.InputStream JavaDoc;
45 import java.io.ObjectInput JavaDoc;
46 import java.io.ObjectOutput JavaDoc;
47 import java.io.OutputStream JavaDoc;
48
49 import java.sql.SQLException JavaDoc;
50
51 import com.quadcap.sql.io.ObjectInputStream;
52 import com.quadcap.sql.io.ObjectOutputStream;
53 import com.quadcap.sql.io.Extern;
54
55 import com.quadcap.sql.file.BlockAccess;
56 import com.quadcap.sql.file.BlockFile;
57 import com.quadcap.sql.file.Datafile;
58 import com.quadcap.sql.file.Log;
59 import com.quadcap.sql.file.PageManager;
60 import com.quadcap.sql.file.SubPageManager;
61
62 import com.quadcap.sql.types.Value;
63 import com.quadcap.sql.types.ValueBlob;
64
65 import com.quadcap.util.Debug;
66
67 import com.quadcap.io.IO;
68  
69 /**
70  * Log step to insert a BLOB value into the database.
71  *
72  * @author Stan Bailes
73  */
74 public class InsertBlob extends LogStep implements Externalizable JavaDoc {
75     long tempBlock;
76     long permBlock;
77
78     /**
79      * Default constructor for serialization
80      */
81     public InsertBlob() {}
82
83     /**
84      * Construct InsertBlob for a given blob
85      */
86     public InsertBlob(Session session, ValueBlob blob)
87         throws IOException JavaDoc
88     {
89         super(session);
90
91         if (blob.getBytesVal() != null) {
92             blob.passivate(session.getDatabase(), session.getTransactionId());
93         }
94     this.tempBlock = blob.getTempBlock();
95     this.permBlock = blob.getPermBlock();
96     }
97
98     /**
99      * LogStep.redo():
100      */
101     public void redo(Session session) throws IOException JavaDoc, SQLException JavaDoc {
102     Log log = session.getLog();
103     if (session.getConnection().inRecovery() && tempBlock >= 0) {
104         BlockFile perm = session.getFile();
105         BlockFile temp = session.getDatabase().getTempFile();
106         InputStream JavaDoc is = temp.getInputStream(tempBlock);
107
108         long newPermBlock = perm.newPage();
109         OutputStream JavaDoc os = perm.getOutputStream(newPermBlock);
110             IO.copyStream(is, os);
111         os.close();
112         is.close();
113
114         log.putRowMap(permBlock, newPermBlock);
115         permBlock = newPermBlock;
116     }
117     session.getDatabase().addMorgue(permBlock, session.getTransactionId());
118     }
119
120     public void undo(Session session) throws IOException JavaDoc, SQLException JavaDoc {
121         final Database db = session.getDatabase();
122     final BlockFile file = session.getFile();
123
124     file.freeStream(permBlock);
125     db.delMorgue(permBlock);
126     }
127
128     public void prepare(Session session) throws IOException JavaDoc {
129     }
130     
131     public void readExternal(ObjectInput JavaDoc in)
132     throws IOException JavaDoc, ClassNotFoundException JavaDoc
133     {
134     super.readExternal(in);
135     tempBlock = in.readLong();
136     permBlock = in.readLong();
137     }
138     
139     public void writeExternal(ObjectOutput JavaDoc out) throws IOException JavaDoc {
140     super.writeExternal(out);
141     out.writeLong(tempBlock);
142     out.writeLong(permBlock);
143     }
144
145     //#ifdef DEBUG
146 public String JavaDoc toString() {
147     StringBuffer JavaDoc sb = new StringBuffer JavaDoc(super.toString());
148         sb.append(" InsertBlob(");
149     sb.append(Long.toString(tempBlock));
150     sb.append(',');
151     sb.append(Long.toString(permBlock));
152     sb.append(')');
153     return sb.toString();
154     }
155     //#endif
156
157     static Extern extern;
158     public void setExtern(Extern extern) { InsertBlob.extern = extern; }
159     public Extern getExtern() { return extern; }
160
161     public void discard(Datafile db) throws IOException JavaDoc {
162         db.getTempFile(false).freeSegment(tempBlock);
163         db.releaseTempFile(); // Release refcount obtained when the blob was created
164 }
165 }
166
Popular Tags