1/*
2 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. 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.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.rowset.internal;
27
28import java.sql.*;
29import java.io.*;
30import java.util.Arrays;
31
32/**
33 * The abstract base class from which the classes <code>Row</code>
34 * The class <code>BaseRow</code> stores
35 * a row's original values as an array of <code>Object</code>
36 * values, which can be retrieved with the method <code>getOrigRow</code>.
37 * This class also provides methods for getting and setting individual
38 * values in the row.
39 * <P>
40 * A row's original values are the values it contained before it was last
41 * modified.  For example, when the <code>CachedRowSet</code>method
42 * <code>acceptChanges</code> is called, it will reset a row's original
43 * values to be the row's current values.  Then, when the row is modified,
44 * the values that were previously the current values will become the row's
45 * original values (the values the row had immediately before it was modified).
46 * If a row has not been modified, its original values are its initial values.
47 * <P>
48 * Subclasses of this class contain more specific details, such as
49 * the conditions under which an exception is thrown or the bounds for
50 * index parameters.
51 */
52public abstract class BaseRow implements Serializable, Cloneable {
53
54/**
55 * Specify the serialVersionUID
56 */
57private static final long serialVersionUID = 4152013523511412238L;
58
59/**
60 * The array containing the original values for this <code>BaseRow</code>
61 * object.
62 * @serial
63 */
64    protected Object[] origVals;
65
66/**
67 * Retrieves the values that this row contained immediately
68 * prior to its last modification.
69 *
70 * @return an array of <code>Object</code> values containing this row's
71 * original values
72 */
73    public Object[] getOrigRow() {
74        Object[] origRow = this.origVals;
75        return (origRow == null) ? null: Arrays.copyOf(origRow, origRow.length);
76    }
77
78/**
79 * Retrieves the array element at the given index, which is
80 * the original value of column number <i>idx</i> in this row.
81 *
82 * @param idx the index of the element to return
83 * @return the <code>Object</code> value at the given index into this
84 *         row's array of original values
85 * @throws SQLException if there is an error
86 */
87    public abstract Object getColumnObject(int idx) throws SQLException;
88
89/**
90 * Sets the element at the given index into this row's array of
91 * original values to the given value.  Implementations of the classes
92 * <code>Row</code> and determine what happens
93 * when the cursor is on the insert row and when it is on any other row.
94 *
95 * @param idx the index of the element to be set
96 * @param obj the <code>Object</code> to which the element at index
97 *              <code>idx</code> to be set
98 * @throws SQLException if there is an error
99 */
100    public abstract void setColumnObject(int idx, Object obj) throws SQLException;
101}
102