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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      */
equals(Object obj)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      */
getBytes()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       */
toString()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       */
hashCode()118      int hashCode();
119 
120 }
121