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1   /**
2    * JDBM LICENSE v1.00
3    *
4    * Redistribution and use of this software and associated documentation
5    * ("Software"), with or without modification, are permitted provided
6    * that the following conditions are met:
7    *
8    * 1. Redistributions of source code must retain copyright
9    *    statements and notices.  Redistributions must also contain a
10   *    copy of this document.
11   *
12   * 2. Redistributions in binary form must reproduce the
13   *    above copyright notice, this list of conditions and the
14   *    following disclaimer in the documentation and/or other
15   *    materials provided with the distribution.
16   *
17   * 3. The name "JDBM" must not be used to endorse or promote
18   *    products derived from this Software without prior written
19   *    permission of Cees de Groot.  For written permission,
20   *    please contact cg@cdegroot.com.
21   *
22   * 4. Products derived from this Software may not be called "JDBM"
23   *    nor may "JDBM" appear in their names without prior written
24   *    permission of Cees de Groot.
25   *
26   * 5. Due credit should be given to the JDBM Project
27   *    (http://jdbm.sourceforge.net/).
28   *
29   * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS
30   * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
31   * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
32   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
33   * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
34   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
35   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
36   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
38   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
39   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
40   * OF THE POSSIBILITY OF SUCH DAMAGE.
41   *
42   * Copyright 2000 (C) Cees de Groot. All Rights Reserved.
43   * Copyright 2000-2001 (C) Alex Boisvert. All Rights Reserved.
44   * Contributions are Copyright (C) 2000 by their associated contributors.
45   *
46   * $Id: RecordManager.java,v 1.3 2005/06/25 23:12:31 doomdark Exp $
47   */
48  
49  package jdbm;
50  
51  import java.io.IOException;
52  import jdbm.helper.Serializer;
53  
54  /**
55   *  An interface to manages records, which are uninterpreted blobs of data.
56   *  <p>
57   *  The set of record operations is simple: fetch, insert, update and delete.
58   *  Each record is identified using a "rowid" and contains a byte[] data block.
59   *  Rowids are returned on inserts and you can store them someplace safe
60   *  to be able to get  back to them.  Data blocks can be as long as you wish,
61   *  and may have lengths different from the original when updating.
62   *
63   * @author <a href="mailto:boisvert@intalio.com">Alex Boisvert</a>
64   * @author <a href="cg@cdegroot.com">Cees de Groot</a>
65   * @version $Id: RecordManager.java,v 1.3 2005/06/25 23:12:31 doomdark Exp $
66   */
67  public interface RecordManager
68  {
69  
70      /**
71       * Reserved slot for name directory.
72       */
73      public static final int NAME_DIRECTORY_ROOT = 0;
74  
75  
76      /**
77       *  Inserts a new record using standard java object serialization.
78       *
79       *  @param obj the object for the new record.
80       *  @return the rowid for the new record.
81       *  @throws IOException when one of the underlying I/O operations fails.
82       */
83      public abstract long insert( Object obj )
84          throws IOException;
85  
86      
87      /**
88       *  Inserts a new record using a custom serializer.
89       *
90       *  @param obj the object for the new record.
91       *  @param serializer a custom serializer
92       *  @return the rowid for the new record.
93       *  @throws IOException when one of the underlying I/O operations fails.
94       */
95      public abstract long insert( Object obj, Serializer serializer )
96          throws IOException;
97  
98  
99      /**
100      *  Deletes a record.
101      *
102      *  @param recid the rowid for the record that should be deleted.
103      *  @throws IOException when one of the underlying I/O operations fails.
104      */
105     public abstract void delete( long recid )
106         throws IOException;
107 
108 
109     /**
110      *  Updates a record using standard java object serialization.
111      *
112      *  @param recid the recid for the record that is to be updated.
113      *  @param obj the new object for the record.
114      *  @throws IOException when one of the underlying I/O operations fails.
115      */
116     public abstract void update( long recid, Object obj )
117         throws IOException;
118 
119 
120     /**
121      *  Updates a record using a custom serializer.
122      *
123      *  @param recid the recid for the record that is to be updated.
124      *  @param obj the new object for the record.
125      *  @param serializer a custom serializer
126      *  @throws IOException when one of the underlying I/O operations fails.
127      */
128     public abstract void update( long recid, Object obj, Serializer serializer )
129         throws IOException;
130 
131     
132     /**
133      *  Fetches a record using standard java object serialization.
134      *
135      *  @param recid the recid for the record that must be fetched.
136      *  @return the object contained in the record.
137      *  @throws IOException when one of the underlying I/O operations fails.
138      */
139     public abstract Object fetch( long recid )
140         throws IOException;
141 
142 
143     /**
144      *  Fetches a record using a custom serializer.
145      *
146      *  @param recid the recid for the record that must be fetched.
147      *  @param serializer a custom serializer
148      *  @return the object contained in the record.
149      *  @throws IOException when one of the underlying I/O operations fails.
150      */
151     public abstract Object fetch( long recid, Serializer serializer )
152         throws IOException;
153 
154 
155     /**
156      *  Closes the record manager.
157      *
158      *  @throws IOException when one of the underlying I/O operations fails.
159      */
160     public abstract void close()
161         throws IOException;
162 
163 
164     /**
165      *  Returns the number of slots available for "root" rowids. These slots
166      *  can be used to store special rowids, like rowids that point to
167      *  other rowids. Root rowids are useful for bootstrapping access to
168      *  a set of data.
169      */
170     public abstract int getRootCount();
171 
172 
173     /**
174      *  Returns the indicated root rowid.
175      *
176      *  @see #getRootCount
177      */
178     public abstract long getRoot( int id )
179         throws IOException;
180 
181 
182     /**
183      *  Sets the indicated root rowid.
184      *
185      *  @see #getRootCount
186      */
187     public abstract void setRoot( int id, long rowid )
188         throws IOException;
189 
190 
191     /**
192      * Commit (make persistent) all changes since beginning of transaction.
193      */
194     public abstract void commit()
195         throws IOException;
196 
197 
198     /**
199      * Rollback (cancel) all changes since beginning of transaction.
200      */
201     public abstract void rollback()
202         throws IOException;
203 
204 
205 
206 
207     /**
208      * Obtain the record id of a named object. Returns 0 if named object
209      * doesn't exist.
210      */
211     public abstract long getNamedObject( String name )
212         throws IOException;
213 
214 
215     /**
216      * Set the record id of a named object.
217      */
218     public abstract void setNamedObject( String name, long recid )
219         throws IOException;
220 
221 }
222