1 /*
2 * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package java.sql;
27
28 /**
29 *
30 * The representation (mapping) in the Java programming language of an SQL ROWID
31 * value. An SQL ROWID is a built-in type, a value of which can be thought of as
32 * an address for its identified row in a database table. Whether that address
33 * is logical or, in any respects, physical is determined by its originating data
34 * source.
35 * <p>
36 * Methods in the interfaces <code>ResultSet</code>, <code>CallableStatement</code>,
37 * and <code>PreparedStatement</code>, such as <code>getRowId</code> and <code>setRowId</code>
38 * allow a programmer to access a SQL <code>ROWID</code> value. The <code>RowId</code>
39 * interface provides a method
40 * for representing the value of the <code>ROWID</code> as a byte array or as a
41 * <code>String</code>.
42 * <p>
43 * The method <code>getRowIdLifetime</code> in the interface <code>DatabaseMetaData</code>,
44 * can be used
45 * to determine if a <code>RowId</code> object remains valid for the duration of the transaction in
46 * which the <code>RowId</code> was created, the duration of the session in which
47 * the <code>RowId</code> was created,
48 * or, effectively, for as long as its identified row is not deleted. In addition
49 * to specifying the duration of its valid lifetime outside its originating data
50 * source, <code>getRowIdLifetime</code> specifies the duration of a <code>ROWID</code>
51 * value's valid lifetime
52 * within its originating data source. In this, it differs from a large object,
53 * because there is no limit on the valid lifetime of a large object within its
54 * originating data source.
55 * <p>
56 * All methods on the <code>RowId</code> interface must be fully implemented if the
57 * JDBC driver supports the data type.
58 *
59 * @see java.sql.DatabaseMetaData
60 * @since 1.6
61 */
62
63 public interface RowId {
64 /**
65 * Compares this <code>RowId</code> to the specified object. The result is
66 * <code>true</code> if and only if the argument is not null and is a RowId
67 * object that represents the same ROWID as this object.
68 * <p>
69 * It is important
70 * to consider both the origin and the valid lifetime of a <code>RowId</code>
71 * when comparing it to another <code>RowId</code>. If both are valid, and
72 * both are from the same table on the same data source, then if they are equal
73 * they identify
74 * the same row; if one or more is no longer guaranteed to be valid, or if
75 * they originate from different data sources, or different tables on the
76 * same data source, they may be equal but still
77 * not identify the same row.
78 *
79 * @param obj the <code>Object</code> to compare this <code>RowId</code> object
80 * against.
81 * @return true if the <code>RowId</code>s are equal; false otherwise
82 * @since 1.6
83 */
84 boolean equals(Object obj);
85
86 /**
87 * Returns an array of bytes representing the value of the SQL <code>ROWID</code>
88 * designated by this <code>java.sql.RowId</code> object.
89 *
90 * @return an array of bytes, whose length is determined by the driver supplying
91 * the connection, representing the value of the ROWID designated by this
92 * java.sql.RowId object.
93 */
94 byte[] getBytes();
95
96 /**
97 * Returns a String representing the value of the SQL ROWID designated by this
98 * <code>java.sql.RowId</code> object.
99 * <p>
100 *Like <code>java.sql.Date.toString()</code>
101 * returns the contents of its DATE as the <code>String</code> "2004-03-17"
102 * rather than as DATE literal in SQL (which would have been the <code>String</code>
103 * DATE "2004-03-17"), toString()
104 * returns the contents of its ROWID in a form specific to the driver supplying
105 * the connection, and possibly not as a <code>ROWID</code> literal.
106 *
107 * @return a String whose format is determined by the driver supplying the
108 * connection, representing the value of the <code>ROWID</code> designated
109 * by this <code>java.sql.RowId</code> object.
110 */
111 String toString();
112
113 /**
114 * Returns a hash code value of this <code>RowId</code> object.
115 *
116 * @return a hash code for the <code>RowId</code>
117 */
118 int hashCode();
119
120 }
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