01: /*
02: * Copyright 2003 Sun Microsystems, Inc. All Rights Reserved.
03: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
04: *
05: * This code is free software; you can redistribute it and/or modify it
06: * under the terms of the GNU General Public License version 2 only, as
07: * published by the Free Software Foundation. Sun designates this
08: * particular file as subject to the "Classpath" exception as provided
09: * 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 com.sun.rowset.internal;
27:
28: import java.sql.*;
29: import java.io.*;
30:
31: /**
32: * The abstract base class from which the classes <code>Row</code>
33: * The class <code>BaseRow</code> stores
34: * a row's original values as an array of <code>Object</code>
35: * values, which can be retrieved with the method <code>getOrigRow</code>.
36: * This class also provides methods for getting and setting individual
37: * values in the row.
38: * <P>
39: * A row's original values are the values it contained before it was last
40: * modified. For example, when the <code>CachedRowSet</code>method
41: * <code>acceptChanges</code> is called, it will reset a row's original
42: * values to be the row's current values. Then, when the row is modified,
43: * the values that were previously the current values will become the row's
44: * original values (the values the row had immediately before it was modified).
45: * If a row has not been modified, its original values are its initial values.
46: * <P>
47: * Subclasses of this class contain more specific details, such as
48: * the conditions under which an exception is thrown or the bounds for
49: * index parameters.
50: */
51: public abstract class BaseRow implements Serializable, Cloneable {
52:
53: /**
54: * The array containing the original values for this <code>BaseRow</code>
55: * object.
56: * @serial
57: */
58: protected Object[] origVals;
59:
60: /**
61: * Retrieves the values that this row contained immediately
62: * prior to its last modification.
63: *
64: * @return an array of <code>Object</code> values containing this row's
65: * original values
66: */
67: public Object[] getOrigRow() {
68: return origVals;
69: }
70:
71: /**
72: * Retrieves the array element at the given index, which is
73: * the original value of column number <i>idx</i> in this row.
74: *
75: * @param idx the index of the element to return
76: * @return the <code>Object</code> value at the given index into this
77: * row's array of original values
78: * @throws <code>SQLException</code> if there is an error
79: */
80: public abstract Object getColumnObject(int idx) throws SQLException;
81:
82: /**
83: * Sets the element at the given index into this row's array of
84: * original values to the given value. Implementations of the classes
85: * <code>Row</code> and determine what happens
86: * when the cursor is on the insert row and when it is on any other row.
87: *
88: * @param idx the index of the element to be set
89: * @param obj the <code>Object</code> to which the element at index
90: * <code>idx</code> to be set
91: * @throws <code>SQLException</code> if there is an error
92: */
93: public abstract void setColumnObject(int idx, Object obj)
94: throws SQLException;
95: }
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