FULL PRODUCT VERSION :
java version "1.5.0_05"

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
undoInsert() in CachedRowSet cannot delete the first row.
assuming an empty CacheRowSet and inserting TWO new rows, doing:

crs.first();
crs.undoInsert();

removes the SECOND row. If more rows are inserted,

crs.absolute(2);
crs.undoInsert();

removes the THIRD row and so on.
The first row cannot be removed, since doing

crs.beforeFirst();
crs.undoInsert();

results in SQLException: Invalid cursor position.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
        try
        {
            dataRowSet.beforeFirst();
            dataRowSet.moveToInsertRow();
            dataRowSet.updateXXX(...., .....)
             ..... // Make all the necessary updates
            dataRowSet.insertRow();
            dataRowSet.moveToCurrentRow();

            dataRowSet.first();
            dataRowSet.undoInsert();
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        }

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
crs.first();
crs.undoInsert();

Should remove the topmost (1st) row in a cached row set (assuming it is an inserted row) instead of removing the second one.

crs.absolute(2);
crs.undoInsert();

Should remove the 2nd row in a cached row set (assuming it is an inserted row) instead of removing the third one, and so on....
ACTUAL -
crs.first();
crs.undoInsert();

Removes the second row in a cached row set (or throws ArrayIndexOutOfBoundsException if the second row does not exist) instead of removing the 1st row.

crs.absolute(2);
crs.undoInsert();

Removes the third row in a cached row set (or throws ArrayIndexOutOfBoundsException if the thirdrow does not exist) instead of removing the 2nd row.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: Array index out of range: 1
        at java.util.Vector.remove(Vector.java:791)
        at com.sun.rowset.CachedRowSetImpl.undoInsert(CachedRowSetImpl.java:1026)
        at TEST.CRSTest.removeButtonActionPerformed(CRSTest.java:72)
        at TEST.CRSTest.access$100(CRSTest.java:8)
        at TEST.CRSTest$2.actionPerformed(CRSTest.java:58)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1957)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2280)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:377)
        at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:232)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:234)
        at java.awt.Component.processMouseEvent(Component.java:5957)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3282)
        at java.awt.Component.processEvent(Component.java:5722)
        at java.awt.Container.processEvent(Container.java:1960)
        at java.awt.Component.dispatchEventImpl(Component.java:4365)
        at java.awt.Container.dispatchEventImpl(Container.java:2018)
        at java.awt.Component.dispatchEvent(Component.java:4195)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4222)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3886)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3816)
        at java.awt.Container.dispatchEventImpl(Container.java:2004)
        at java.awt.Window.dispatchEventImpl(Window.java:2300)
        at java.awt.Component.dispatchEvent(Component.java:4195)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package TEST;

import MAIN.CORE.ConnectionManager;
import com.sun.rowset.CachedRowSetImpl;
import java.sql.Connection;
import java.sql.SQLException;
import javax.sql.rowset.CachedRowSet;

public class CRSTest extends javax.swing.JFrame
{
    private ConnectionManager connectionManager = new ConnectionManager();
    private Connection connection = // CONNECTION PROPERTIES
    private CachedRowSet dataRowSet;
    
    public CRSTest()
    {
        // This CachedRowSet is meant to be empty
        // to better demonstrate the scenario, the
        // SQL Select Statement should return no rows.
        dataRowSet = new CachedRowSetImpl();
        dataRowSet.setCommand("SELECT STRING");
        dataRowSet.execute(connection);
        
        initComponents();
        
        try
        {
            dataRowSet.beforeFirst();
            while (dataRowSet.next())
            {
                System.out.println("row: "+dataRowSet.getRow()+" religion_id: "+dataRowSet.getString("religion_id"));
            }
            System.out.println("");
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        }
    }
    
// <editor-fold defaultstate="collapsed" desc=" Generated Code ">
    private void initComponents()
    {
        addButton = new javax.swing.JButton();
        removeButton = new javax.swing.JButton();
        
        getContentPane().setLayout(new java.awt.GridLayout(2, 0));
        
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        addButton.setText("Add to TOP");
        addButton.addActionListener(new java.awt.event.ActionListener()
        {
            public void actionPerformed(java.awt.event.ActionEvent evt)
            {
                addButtonActionPerformed(evt);
            }
        });
        
        getContentPane().add(addButton);
        
        removeButton.setText("Remove from TOP");
        removeButton.addActionListener(new java.awt.event.ActionListener()
        {
            public void actionPerformed(java.awt.event.ActionEvent evt)
            {
                removeButtonActionPerformed(evt);
            }
        });
        
        getContentPane().add(removeButton);
        
        pack();
    }// </editor-fold>
    
    private void removeButtonActionPerformed(java.awt.event.ActionEvent evt)
    {
        try
        {
            dataRowSet.beforeFirst();
            dataRowSet.undoInsert();
            
            dataRowSet.beforeFirst();
            while (dataRowSet.next())
            {
                System.out.println("row: "+dataRowSet.getRow()+" religion_id: "+dataRowSet.getString("religion_id"));
            }
            System.out.println("");
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        }
    }
    
    private void addButtonActionPerformed(java.awt.event.ActionEvent evt)
    {
        try
        {
            dataRowSet.beforeFirst();
            dataRowSet.moveToInsertRow();
            dataRowSet.updateInt("religion_id", dataRowSet.size());
            dataRowSet.updateString("description", "");
            dataRowSet.insertRow();
            dataRowSet.moveToCurrentRow();
            
            dataRowSet.beforeFirst();
            while (dataRowSet.next())
            {
                System.out.println("row: "+dataRowSet.getRow()+" religion_id: "+dataRowSet.getString("religion_id"));
            }
            System.out.println("");
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        }
    }
    
    public static void main(String args[])
    {
        new ConnectionManager().lookupConnections();
        
        java.awt.EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                new CRSTest().setVisible(true);
            }
        });
    }
// Variables declaration - do not modify
    private javax.swing.JButton addButton;
    private javax.swing.JButton removeButton;
// End of variables declaration
}
---------- END SOURCE ----------