Source code: com/virtuosotechnologies/asaph/model/SongOperation.java
1 /*
2 ================================================================================
3
4 FILE: SongOperation.java
5
6 PROJECT:
7
8 Asaph
9
10 CONTENTS:
11
12 An operation to perform on songs
13
14 PROGRAMMERS:
15
16 Daniel Azuma (DA) <dazuma@kagi.com>
17
18 COPYRIGHT:
19
20 Copyright (C) 2003 Daniel Azuma (dazuma@kagi.com)
21
22 This program is free software; you can redistribute it and/or
23 modify it under the terms of the GNU General Public License as
24 published by the Free Software Foundation; either version 2
25 of the License, or (at your option) any later version.
26
27 This program is distributed in the hope that it will be useful,
28 but WITHOUT ANY WARRANTY; without even the implied warranty of
29 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 GNU General Public License for more details.
31
32 You should have received a copy of the GNU General Public
33 License along with this program; if not, write to
34 Free Software Foundation, Inc.
35 59 Temple Place, Suite 330
36 Boston, MA 02111-1307 USA
37
38 ================================================================================
39 */
40
41
42 package com.virtuosotechnologies.asaph.model;
43
44
45 /**
46 * An operation to perform on SongIDResultSets.
47 * This interface merely specifies that this object implements an operation. Most
48 * operation also implement a particular OpSemantics interface to indicate
49 * to the database implementation the kind of operation, so the database can
50 * substitute an optimized implementation if it so chooses.
51 */
52 public interface SongOperation
53 {
54 /**
55 * Performs the operation on the given result set.
56 *
57 * @param resultSet the SongIDResultSet
58 * @exception SongDatabaseFailedException Catch-all exception for database-related
59 * problems. This will often have a cause exception, which may be exceptions
60 * like IOException or SQLException.
61 */
62 public void perform(
63 SongIDResultSet resultSet)
64 throws
65 SongDatabaseFailedException;
66
67
68 /**
69 * The equals method should return true if the given object is a SongOperation
70 * with the same semantics as this one. (i.e. it would perform the same operation.)
71 * This may be used to optimize performance. It is always safe to return false from
72 * this method, if the semantics of the given object cannot be determined.
73 * (This is similar to the equals method in java.util.Comparator.)
74 * As a corollary, it is safe just to fall back on the default implementation
75 * inherited from java.lang.Object.
76 *
77 * @param obj object to test
78 * @return true if the object is equal
79 */
80 public boolean equals(
81 Object obj);
82 }