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 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package java.sql;

/**

 *

 * The representation (mapping) in the Java programming language of an SQL ROWID

 * value. An SQL ROWID is a built-in type, a value of which can be thought of as

 * an address  for its identified row in a database table. Whether that address

 * is logical or, in any  respects, physical is determined by its originating data

 * source.

 * <p>

 * Methods in the interfaces <code>ResultSet</code>, <code>CallableStatement</code>,

 * and <code>PreparedStatement</code>, such as <code>getRowId</code> and <code>setRowId</code>

 * allow a programmer to access a SQL <code>ROWID</code>  value. The <code>RowId</code>

 * interface provides a method

 * for representing the value of the <code>ROWID</code> as a byte array or as a

 * <code>String</code>.

 * <p>

 * The method <code>getRowIdLifetime</code> in the interface <code>DatabaseMetaData</code>,

 * can be used

 * to determine if a <code>RowId</code> object remains valid for the duration of the transaction in

 * which  the <code>RowId</code> was created, the duration of the session in which

 * the <code>RowId</code> was created,

 * or, effectively, for as long as its identified row is not deleted. In addition

 * to specifying the duration of its valid lifetime outside its originating data

 * source, <code>getRowIdLifetime</code> specifies the duration of a <code>ROWID</code>

 * value's valid lifetime

 * within its originating data source. In this, it differs from a large object,

 * because there is no limit on the valid lifetime of a large  object within its

 * originating data source.

 * <p>

 * All methods on the <code>RowId</code> interface must be fully implemented if the

 * JDBC driver supports the data type.

 *

 * @see java.sql.DatabaseMetaData

 * @since 1.6

 */

public interface RowId {

    /**

     * Compares this <code>RowId</code> to the specified object. The result is

     * <code>true</code> if and only if the argument is not null and is a RowId

     * object that represents the same ROWID as  this object.

     * <p>

     * It is important

     * to consider both the origin and the valid lifetime of a <code>RowId</code>

     * when comparing it to another <code>RowId</code>. If both are valid, and

     * both are from the same table on the same data source, then if they are equal

     * they identify

     * the same row; if one or more is no longer guaranteed to be valid, or if

     * they originate from different data sources, or different tables on the

     * same data source, they  may be equal but still

     * not identify the same row.

     *

     * @param obj the <code>Object</code> to compare this <code>RowId</code> object

     *     against.

     * @return true if the <code>RowId</code>s are equal; false otherwise

     * @since 1.6

     */

    boolean equals(Object obj);

    /**

     * Returns an array of bytes representing the value of the SQL <code>ROWID</code>

     * designated by this <code>java.sql.RowId</code> object.

     *

     * @return an array of bytes, whose length is determined by the driver supplying

     *     the connection, representing the value of the ROWID designated by this

     *     java.sql.RowId object.

     */

     byte[] getBytes();

     /**

      * Returns a String representing the value of the SQL ROWID designated by this

      * <code>java.sql.RowId</code> object.

      * <p>

      *Like <code>java.sql.Date.toString()</code>

      * returns the contents of its DATE as the <code>String</code> "2004-03-17"

      * rather than as  DATE literal in SQL (which would have been the <code>String</code>

      * DATE "2004-03-17"), toString()

      * returns the contents of its ROWID in a form specific to the driver supplying

      * the connection, and possibly not as a <code>ROWID</code> literal.

      *

      * @return a String whose format is determined by the driver supplying the

      *     connection, representing the value of the <code>ROWID</code> designated

      *     by this <code>java.sql.RowId</code>  object.

      */

     String toString();

     /**

      * Returns a hash code value of this <code>RowId</code> object.

      *

      * @return a hash code for the <code>RowId</code>

      */

     int hashCode();

}