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 

    26 package com.sun.rowset.internal;

    27 

    28 import java.sql.*;

    29 import java.io.*;

    30 import 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  */

    52 public abstract class BaseRow implements Serializable, Cloneable {

    53 

    54 /**

    55  * Specify the serialVersionUID

    56  */

    57 private 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 }