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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package javax.swing.plaf.basic;

import sun.swing.DefaultLookup;
import sun.swing.UIAction;

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.plaf.*;
import javax.swing.text.Position;

import java.awt.*;
import java.awt.event.*;
import java.awt.datatransfer.Transferable;
import java.awt.geom.Point2D;

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeEvent;

import sun.swing.SwingUtilities2;
import javax.swing.plaf.basic.DragRecognitionSupport.BeforeDrag;

An extensible implementation of ListUI. 
 BasicListUI instances cannot be shared between multiple lists. 
Author:
Hans Muller, Philip Milne, Shannon Hickey (drag and drop)/**
 * An extensible implementation of {@code ListUI}.
 * <p>
 * {@code BasicListUI} instances cannot be shared between multiple
 * lists.
 *
 * @author Hans Muller
 * @author Philip Milne
 * @author Shannon Hickey (drag and drop)
 */
public class BasicListUI extends ListUI
{
    private static final StringBuilder BASELINE_COMPONENT_KEY =
        new StringBuilder("List.baselineComponent");

    
The instance of JList. /**
     * The instance of {@code JList}.
     */
    protected JList<Object> list = null;
    
The instance of CellRendererPane. /**
     * The instance of {@code CellRendererPane}.
     */
    protected CellRendererPane rendererPane;

    // Listeners that this UI attaches to the JList
    
FocusListener that attached to JList. /**
     * {@code FocusListener} that attached to {@code JList}.
     */
    protected FocusListener focusListener;
    
MouseInputListener that attached to JList. /**
     * {@code MouseInputListener} that attached to {@code JList}.
     */
    protected MouseInputListener mouseInputListener;
    
ListSelectionListener that attached to JList. /**
     * {@code ListSelectionListener} that attached to {@code JList}.
     */
    protected ListSelectionListener listSelectionListener;
    
ListDataListener that attached to JList. /**
     * {@code ListDataListener} that attached to {@code JList}.
     */
    protected ListDataListener listDataListener;
    
PropertyChangeListener that attached to JList. /**
     * {@code PropertyChangeListener} that attached to {@code JList}.
     */
    protected PropertyChangeListener propertyChangeListener;
    private Handler handler;

    
The array of cells' height
/**
     * The array of cells' height
     */
    protected int[] cellHeights = null;
    
The height of cell.
/**
     * The height of cell.
     */
    protected int cellHeight = -1;
    
The width of cell.
/**
     * The width of cell.
     */
    protected int cellWidth = -1;
    
The value represents changes to JList model. /**
     * The value represents changes to {@code JList} model.
     */
    protected int updateLayoutStateNeeded = modelChanged;
    
Height of the list. When asked to paint, if the current size of
the list differs, this will update the layout state.
/**
     * Height of the list. When asked to paint, if the current size of
     * the list differs, this will update the layout state.
     */
    private int listHeight;

    
Width of the list. When asked to paint, if the current size of
the list differs, this will update the layout state.
/**
     * Width of the list. When asked to paint, if the current size of
     * the list differs, this will update the layout state.
     */
    private int listWidth;

    
The layout orientation of the list.
/**
     * The layout orientation of the list.
     */
    private int layoutOrientation;

    // Following ivars are used if the list is laying out horizontally

    
Number of columns to create.
/**
     * Number of columns to create.
     */
    private int columnCount;
    
Preferred height to make the list, this is only used if the
the list is layed out horizontally.
/**
     * Preferred height to make the list, this is only used if the
     * the list is layed out horizontally.
     */
    private int preferredHeight;
    
Number of rows per column. This is only used if the row height is
fixed.
/**
     * Number of rows per column. This is only used if the row height is
     * fixed.
     */
    private int rowsPerColumn;

    
The time factor to treate the series of typed alphanumeric key
as prefix for first letter navigation.
/**
     * The time factor to treate the series of typed alphanumeric key
     * as prefix for first letter navigation.
     */
    private long timeFactor = 1000L;

    
Local cache of JList's client property "List.isFileList"
/**
     * Local cache of JList's client property "List.isFileList"
     */
    private boolean isFileList = false;

    
Local cache of JList's component orientation property
/**
     * Local cache of JList's component orientation property
     */
    private boolean isLeftToRight = true;

    /* The bits below define JList property changes that affect layout.
     * When one of these properties changes we set a bit in
     * updateLayoutStateNeeded.  The change is dealt with lazily, see
     * maybeUpdateLayoutState.  Changes to the JLists model, e.g. the
     * models length changed, are handled similarly, see DataListener.
     */

    
The bit relates to model changed property.
/**
     * The bit relates to model changed property.
     */
    protected static final int modelChanged = 1 << 0;
    
The bit relates to selection model changed property.
/**
     * The bit relates to selection model changed property.
     */
    protected static final int selectionModelChanged = 1 << 1;
    
The bit relates to font changed property.
/**
     * The bit relates to font changed property.
     */
    protected static final int fontChanged = 1 << 2;
    
The bit relates to fixed cell width changed property.
/**
     * The bit relates to fixed cell width changed property.
     */
    protected static final int fixedCellWidthChanged = 1 << 3;
    
The bit relates to fixed cell height changed property.
/**
     * The bit relates to fixed cell height changed property.
     */
    protected static final int fixedCellHeightChanged = 1 << 4;
    
The bit relates to prototype cell value changed property.
/**
     * The bit relates to prototype cell value changed property.
     */
    protected static final int prototypeCellValueChanged = 1 << 5;
    
The bit relates to cell renderer changed property.
/**
     * The bit relates to cell renderer changed property.
     */
    protected static final int cellRendererChanged = 1 << 6;
    private static final int layoutOrientationChanged = 1 << 7;
    private static final int heightChanged = 1 << 8;
    private static final int widthChanged = 1 << 9;
    private static final int componentOrientationChanged = 1 << 10;

    private static final int DROP_LINE_THICKNESS = 2;

    static void loadActionMap(LazyActionMap map) {
        map.put(new Actions(Actions.SELECT_PREVIOUS_COLUMN));
        map.put(new Actions(Actions.SELECT_PREVIOUS_COLUMN_EXTEND));
        map.put(new Actions(Actions.SELECT_PREVIOUS_COLUMN_CHANGE_LEAD));
        map.put(new Actions(Actions.SELECT_NEXT_COLUMN));
        map.put(new Actions(Actions.SELECT_NEXT_COLUMN_EXTEND));
        map.put(new Actions(Actions.SELECT_NEXT_COLUMN_CHANGE_LEAD));
        map.put(new Actions(Actions.SELECT_PREVIOUS_ROW));
        map.put(new Actions(Actions.SELECT_PREVIOUS_ROW_EXTEND));
        map.put(new Actions(Actions.SELECT_PREVIOUS_ROW_CHANGE_LEAD));
        map.put(new Actions(Actions.SELECT_NEXT_ROW));
        map.put(new Actions(Actions.SELECT_NEXT_ROW_EXTEND));
        map.put(new Actions(Actions.SELECT_NEXT_ROW_CHANGE_LEAD));
        map.put(new Actions(Actions.SELECT_FIRST_ROW));
        map.put(new Actions(Actions.SELECT_FIRST_ROW_EXTEND));
        map.put(new Actions(Actions.SELECT_FIRST_ROW_CHANGE_LEAD));
        map.put(new Actions(Actions.SELECT_LAST_ROW));
        map.put(new Actions(Actions.SELECT_LAST_ROW_EXTEND));
        map.put(new Actions(Actions.SELECT_LAST_ROW_CHANGE_LEAD));
        map.put(new Actions(Actions.SCROLL_UP));
        map.put(new Actions(Actions.SCROLL_UP_EXTEND));
        map.put(new Actions(Actions.SCROLL_UP_CHANGE_LEAD));
        map.put(new Actions(Actions.SCROLL_DOWN));
        map.put(new Actions(Actions.SCROLL_DOWN_EXTEND));
        map.put(new Actions(Actions.SCROLL_DOWN_CHANGE_LEAD));
        map.put(new Actions(Actions.SELECT_ALL));
        map.put(new Actions(Actions.CLEAR_SELECTION));
        map.put(new Actions(Actions.ADD_TO_SELECTION));
        map.put(new Actions(Actions.TOGGLE_AND_ANCHOR));
        map.put(new Actions(Actions.EXTEND_TO));
        map.put(new Actions(Actions.MOVE_SELECTION_TO));

        map.put(TransferHandler.getCutAction().getValue(Action.NAME),
                TransferHandler.getCutAction());
        map.put(TransferHandler.getCopyAction().getValue(Action.NAME),
                TransferHandler.getCopyAction());
        map.put(TransferHandler.getPasteAction().getValue(Action.NAME),
                TransferHandler.getPasteAction());
    }

    
Paint one List cell: compute the relevant state, get the "rubber stamp" cell renderer component, and then use the CellRendererPane to paint it. Subclasses may want to override this method rather than paint(). 
Params:
g – an instance of Graphics
row – a row
rowBounds – a bounding rectangle to render to
cellRenderer – a list of ListCellRenderer
dataModel – a list model
selModel – a selection model
leadIndex – a lead index
See Also:
paint/**
     * Paint one List cell: compute the relevant state, get the "rubber stamp"
     * cell renderer component, and then use the {@code CellRendererPane} to paint it.
     * Subclasses may want to override this method rather than {@code paint()}.
     *
     * @param g an instance of {@code Graphics}
     * @param row a row
     * @param rowBounds a bounding rectangle to render to
     * @param cellRenderer a list of {@code ListCellRenderer}
     * @param dataModel a list model
     * @param selModel a selection model
     * @param leadIndex a lead index
     * @see #paint
     */
    protected void paintCell(
        Graphics g,
        int row,
        Rectangle rowBounds,
        ListCellRenderer<Object> cellRenderer,
        ListModel<Object> dataModel,
        ListSelectionModel selModel,
        int leadIndex)
    {
        Object value = dataModel.getElementAt(row);
        boolean cellHasFocus = list.hasFocus() && (row == leadIndex);
        boolean isSelected = selModel.isSelectedIndex(row);

        Component rendererComponent =
            cellRenderer.getListCellRendererComponent(list, value, row, isSelected, cellHasFocus);

        int cx = rowBounds.x;
        int cy = rowBounds.y;
        int cw = rowBounds.width;
        int ch = rowBounds.height;

        if (isFileList) {
            // Shrink renderer to preferred size. This is mostly used on Windows
            // where selection is only shown around the file name, instead of
            // across the whole list cell.
            int w = Math.min(cw, rendererComponent.getPreferredSize().width + 4);
            if (!isLeftToRight) {
                cx += (cw - w);
            }
            cw = w;
        }

        rendererPane.paintComponent(g, rendererComponent, list, cx, cy, cw, ch, true);
    }


    
Paint the rows that intersect the Graphics objects clipRect.  This
method calls paintCell as necessary.  Subclasses
may want to override these methods.
See Also:
paintCell/**
     * Paint the rows that intersect the Graphics objects clipRect.  This
     * method calls paintCell as necessary.  Subclasses
     * may want to override these methods.
     *
     * @see #paintCell
     */
    public void paint(Graphics g, JComponent c) {
        Shape clip = g.getClip();
        paintImpl(g, c);
        g.setClip(clip);

        paintDropLine(g);
    }

    private void paintImpl(Graphics g, JComponent c)
    {
        switch (layoutOrientation) {
        case JList.VERTICAL_WRAP:
            if (list.getHeight() != listHeight) {
                updateLayoutStateNeeded |= heightChanged;
                redrawList();
            }
            break;
        case JList.HORIZONTAL_WRAP:
            if (list.getWidth() != listWidth) {
                updateLayoutStateNeeded |= widthChanged;
                redrawList();
            }
            break;
        default:
            break;
        }
        maybeUpdateLayoutState();

        ListCellRenderer<Object> renderer = list.getCellRenderer();
        ListModel<Object> dataModel = list.getModel();
        ListSelectionModel selModel = list.getSelectionModel();
        int size;

        if ((renderer == null) || (size = dataModel.getSize()) == 0) {
            return;
        }

        // Determine how many columns we need to paint
        Rectangle paintBounds = g.getClipBounds();

        int startColumn, endColumn;
        if (c.getComponentOrientation().isLeftToRight()) {
            startColumn = convertLocationToColumn(paintBounds.x,
                                                  paintBounds.y);
            endColumn = convertLocationToColumn(paintBounds.x +
                                                paintBounds.width,
                                                paintBounds.y);
        } else {
            startColumn = convertLocationToColumn(paintBounds.x +
                                                paintBounds.width,
                                                paintBounds.y);
            endColumn = convertLocationToColumn(paintBounds.x,
                                                  paintBounds.y);
        }
        int maxY = paintBounds.y + paintBounds.height;
        int leadIndex = adjustIndex(list.getLeadSelectionIndex(), list);
        int rowIncrement = (layoutOrientation == JList.HORIZONTAL_WRAP) ?
                           columnCount : 1;


        for (int colCounter = startColumn; colCounter <= endColumn;
             colCounter++) {
            // And then how many rows in this columnn
            int row = convertLocationToRowInColumn(paintBounds.y, colCounter);
            int rowCount = getRowCount(colCounter);
            int index = getModelIndex(colCounter, row);
            Rectangle rowBounds = getCellBounds(list, index, index);

            if (rowBounds == null) {
                // Not valid, bail!
                return;
            }
            while (row < rowCount && rowBounds.y < maxY &&
                   index < size) {
                rowBounds.height = getHeight(colCounter, row);
                g.setClip(rowBounds.x, rowBounds.y, rowBounds.width,
                          rowBounds.height);
                g.clipRect(paintBounds.x, paintBounds.y, paintBounds.width,
                           paintBounds.height);
                paintCell(g, index, rowBounds, renderer, dataModel, selModel,
                          leadIndex);
                rowBounds.y += rowBounds.height;
                index += rowIncrement;
                row++;
            }
        }
        // Empty out the renderer pane, allowing renderers to be gc'ed.
        rendererPane.removeAll();
    }

    private void paintDropLine(Graphics g) {
        JList.DropLocation loc = list.getDropLocation();
        if (loc == null || !loc.isInsert()) {
            return;
        }

        Color c = DefaultLookup.getColor(list, this, "List.dropLineColor", null);
        if (c != null) {
            g.setColor(c);
            Rectangle rect = getDropLineRect(loc);
            g.fillRect(rect.x, rect.y, rect.width, rect.height);
        }
    }

    private Rectangle getDropLineRect(JList.DropLocation loc) {
        int size = list.getModel().getSize();

        if (size == 0) {
            Insets insets = list.getInsets();
            if (layoutOrientation == JList.HORIZONTAL_WRAP) {
                if (isLeftToRight) {
                    return new Rectangle(insets.left, insets.top, DROP_LINE_THICKNESS, 20);
                } else {
                    return new Rectangle(list.getWidth() - DROP_LINE_THICKNESS - insets.right,
                                         insets.top, DROP_LINE_THICKNESS, 20);
                }
            } else {
                return new Rectangle(insets.left, insets.top,
                                     list.getWidth() - insets.left - insets.right,
                                     DROP_LINE_THICKNESS);
            }
        }

        Rectangle rect = null;
        int index = loc.getIndex();
        boolean decr = false;

        if (layoutOrientation == JList.HORIZONTAL_WRAP) {
            if (index == size) {
                decr = true;
            } else if (index != 0 && convertModelToRow(index)
                                         != convertModelToRow(index - 1)) {

                Rectangle prev = getCellBounds(list, index - 1);
                Rectangle me = getCellBounds(list, index);
                Point p = loc.getDropPoint();

                if (isLeftToRight) {
                    decr = Point2D.distance(prev.x + prev.width,
                                            prev.y + (int)(prev.height / 2.0),
                                            p.x, p.y)
                           < Point2D.distance(me.x,
                                              me.y + (int)(me.height / 2.0),
                                              p.x, p.y);
                } else {
                    decr = Point2D.distance(prev.x,
                                            prev.y + (int)(prev.height / 2.0),
                                            p.x, p.y)
                           < Point2D.distance(me.x + me.width,
                                              me.y + (int)(prev.height / 2.0),
                                              p.x, p.y);
                }
            }

            if (decr) {
                index--;
                rect = getCellBounds(list, index);
                if (isLeftToRight) {
                    rect.x += rect.width;
                } else {
                    rect.x -= DROP_LINE_THICKNESS;
                }
            } else {
                rect = getCellBounds(list, index);
                if (!isLeftToRight) {
                    rect.x += rect.width - DROP_LINE_THICKNESS;
                }
            }

            if (rect.x >= list.getWidth()) {
                rect.x = list.getWidth() - DROP_LINE_THICKNESS;
            } else if (rect.x < 0) {
                rect.x = 0;
            }

            rect.width = DROP_LINE_THICKNESS;
        } else if (layoutOrientation == JList.VERTICAL_WRAP) {
            if (index == size) {
                index--;
                rect = getCellBounds(list, index);
                rect.y += rect.height;
            } else if (index != 0 && convertModelToColumn(index)
                                         != convertModelToColumn(index - 1)) {

                Rectangle prev = getCellBounds(list, index - 1);
                Rectangle me = getCellBounds(list, index);
                Point p = loc.getDropPoint();
                if (Point2D.distance(prev.x + (int)(prev.width / 2.0),
                                     prev.y + prev.height,
                                     p.x, p.y)
                        < Point2D.distance(me.x + (int)(me.width / 2.0),
                                           me.y,
                                           p.x, p.y)) {

                    index--;
                    rect = getCellBounds(list, index);
                    rect.y += rect.height;
                } else {
                    rect = getCellBounds(list, index);
                }
            } else {
                rect = getCellBounds(list, index);
            }

            if (rect.y >= list.getHeight()) {
                rect.y = list.getHeight() - DROP_LINE_THICKNESS;
            }

            rect.height = DROP_LINE_THICKNESS;
        } else {
            if (index == size) {
                index--;
                rect = getCellBounds(list, index);
                rect.y += rect.height;
            } else {
                rect = getCellBounds(list, index);
            }

            if (rect.y >= list.getHeight()) {
                rect.y = list.getHeight() - DROP_LINE_THICKNESS;
            }

            rect.height = DROP_LINE_THICKNESS;
        }

        return rect;
    }

    
Returns the baseline.
Throws:
NullPointerException – {@inheritDoc}
IllegalArgumentException – {@inheritDoc}
See Also:
JComponent.getBaseline(int, int)
Since:
1.6/**
     * Returns the baseline.
     *
     * @throws NullPointerException {@inheritDoc}
     * @throws IllegalArgumentException {@inheritDoc}
     * @see javax.swing.JComponent#getBaseline(int, int)
     * @since 1.6
     */
    public int getBaseline(JComponent c, int width, int height) {
        super.getBaseline(c, width, height);
        int rowHeight = list.getFixedCellHeight();
        UIDefaults lafDefaults = UIManager.getLookAndFeelDefaults();
        Component renderer = (Component)lafDefaults.get(
                BASELINE_COMPONENT_KEY);
        if (renderer == null) {
            @SuppressWarnings("unchecked")
            ListCellRenderer<Object> lcr = (ListCellRenderer)UIManager.get(
                    "List.cellRenderer");

            // fix for 6711072 some LAFs like Nimbus do not provide this
            // UIManager key and we should not through a NPE here because of it
            if (lcr == null) {
                lcr = new DefaultListCellRenderer();
            }
            renderer = lcr.getListCellRendererComponent(
                    list, "a", -1, false, false);
            lafDefaults.put(BASELINE_COMPONENT_KEY, renderer);
        }
        renderer.setFont(list.getFont());
        // JList actually has much more complex behavior here.
        // If rowHeight != -1 the rowHeight is either the max of all cell
        // heights (layout orientation != VERTICAL), or is variable depending
        // upon the cell.  We assume a default size.
        // We could theoretically query the real renderer, but that would
        // not work for an empty model and the results may vary with
        // the content.
        if (rowHeight == -1) {
            rowHeight = renderer.getPreferredSize().height;
        }
        return renderer.getBaseline(Integer.MAX_VALUE, rowHeight) +
                list.getInsets().top;
    }

    
Returns an enum indicating how the baseline of the component
changes as the size changes.
Throws:
NullPointerException – {@inheritDoc}
See Also:
JComponent.getBaseline(int, int)
Since:
1.6/**
     * Returns an enum indicating how the baseline of the component
     * changes as the size changes.
     *
     * @throws NullPointerException {@inheritDoc}
     * @see javax.swing.JComponent#getBaseline(int, int)
     * @since 1.6
     */
    public Component.BaselineResizeBehavior getBaselineResizeBehavior(
            JComponent c) {
        super.getBaselineResizeBehavior(c);
        return Component.BaselineResizeBehavior.CONSTANT_ASCENT;
    }

    
The preferredSize of the list depends upon the layout orientation.

Describes the preferred size for each layout orientation


  

    
Layout Orientation
    
Preferred Size


  

    
JList.VERTICAL
    
The preferredSize of the list is total height of the rows
    and the maximum width of the cells. If JList.fixedCellHeight
    is specified then the total height of the rows is just
    (cellVerticalMargins + fixedCellHeight) * model.getSize() where
    rowVerticalMargins is the space we allocate for drawing
    the yellow focus outline. Similarly if fixedCellWidth is
    specified then we just use that.
  

    
JList.VERTICAL_WRAP
    
If the visible row count is greater than zero, the preferredHeight
    is the maximum cell height * visibleRowCount. If the visible row
    count is <= 0, the preferred height is either the current height
    of the list, or the maximum cell height, whichever is
    bigger. The preferred width is than the maximum cell width *
    number of columns needed. Where the number of columns needs is
    list.height / max cell height. Max cell height is either the fixed
    cell height, or is determined by iterating through all the cells
    to find the maximum height from the ListCellRenderer.
  

    
JList.HORIZONTAL_WRAP
    
If the visible row count is greater than zero, the preferredHeight
    is the maximum cell height * adjustedRowCount. Where
    visibleRowCount is used to determine the number of columns.
    Because this lays out horizontally the number of rows is
    then determined from the column count. For example, lets say
    you have a model with 10 items and the visible row count is 8.
    The number of columns needed to display this is 2, but you no
    longer need 8 rows to display this, you only need 5, thus
    the adjustedRowCount is 5.
    
 If the visible row count is <= 0, the preferred height is dictated by the number of columns, which will be as many as can fit in the width of the JList (width / max cell width), with at least one column. The preferred height then becomes the model size / number of columns * maximum cell height. Max cell height is either the fixed cell height, or is determined by iterating through all the cells to find the maximum height from the ListCellRenderer. 

The above specifies the raw preferred width and height. The resulting
preferred width is the above width + insets.left + insets.right and
the resulting preferred height is the above height + insets.top +
insets.bottom. Where the Insets are determined from
list.getInsets().
Params:
c – The JList component.
Returns:
The total size of the list./**
     * The preferredSize of the list depends upon the layout orientation.
     *
     * <table class="striped">
     * <caption>Describes the preferred size for each layout orientation
     * </caption>
     * <thead>
     *   <tr>
     *     <th scope="col">Layout Orientation
     *     <th scope="col">Preferred Size
     * </thead>
     * <tbody>
     *   <tr>
     *     <th scope="row">JList.VERTICAL
     *     <td>The preferredSize of the list is total height of the rows
     *     and the maximum width of the cells. If JList.fixedCellHeight
     *     is specified then the total height of the rows is just
     *     (cellVerticalMargins + fixedCellHeight) * model.getSize() where
     *     rowVerticalMargins is the space we allocate for drawing
     *     the yellow focus outline. Similarly if fixedCellWidth is
     *     specified then we just use that.
     *   <tr>
     *     <th scope="row">JList.VERTICAL_WRAP
     *     <td>If the visible row count is greater than zero, the preferredHeight
     *     is the maximum cell height * visibleRowCount. If the visible row
     *     count is &lt;= 0, the preferred height is either the current height
     *     of the list, or the maximum cell height, whichever is
     *     bigger. The preferred width is than the maximum cell width *
     *     number of columns needed. Where the number of columns needs is
     *     list.height / max cell height. Max cell height is either the fixed
     *     cell height, or is determined by iterating through all the cells
     *     to find the maximum height from the ListCellRenderer.
     *   <tr>
     *     <th scope="row">JList.HORIZONTAL_WRAP
     *     <td>If the visible row count is greater than zero, the preferredHeight
     *     is the maximum cell height * adjustedRowCount. Where
     *     visibleRowCount is used to determine the number of columns.
     *     Because this lays out horizontally the number of rows is
     *     then determined from the column count. For example, lets say
     *     you have a model with 10 items and the visible row count is 8.
     *     The number of columns needed to display this is 2, but you no
     *     longer need 8 rows to display this, you only need 5, thus
     *     the adjustedRowCount is 5.
     *     <p>
     *     If the visible row count is &lt;= 0, the preferred height is dictated
     *     by the number of columns, which will be as many as can fit in the
     *     width of the {@code JList} (width / max cell width), with at least
     *     one column. The preferred height then becomes the model size / number
     *     of columns * maximum cell height. Max cell height is either the fixed
     *     cell height, or is determined by iterating through all the cells to
     *     find the maximum height from the ListCellRenderer.
     * </tbody>
     * </table>
     *
     * The above specifies the raw preferred width and height. The resulting
     * preferred width is the above width + insets.left + insets.right and
     * the resulting preferred height is the above height + insets.top +
     * insets.bottom. Where the <code>Insets</code> are determined from
     * <code>list.getInsets()</code>.
     *
     * @param c The JList component.
     * @return The total size of the list.
     */
    public Dimension getPreferredSize(JComponent c) {
        maybeUpdateLayoutState();

        int lastRow = list.getModel().getSize() - 1;
        if (lastRow < 0) {
            return new Dimension(0, 0);
        }

        Insets insets = list.getInsets();
        int width = cellWidth * columnCount + insets.left + insets.right;
        int height;

        if (layoutOrientation != JList.VERTICAL) {
            height = preferredHeight;
        }
        else {
            Rectangle bounds = getCellBounds(list, lastRow);

            if (bounds != null) {
                height = bounds.y + bounds.height + insets.bottom;
            }
            else {
                height = 0;
            }
        }
        return new Dimension(width, height);
    }


    
Selected the previous row and force it to be visible.
See Also:
ensureIndexIsVisible.ensureIndexIsVisible/**
     * Selected the previous row and force it to be visible.
     *
     * @see JList#ensureIndexIsVisible
     */
    protected void selectPreviousIndex() {
        int s = list.getSelectedIndex();
        if(s > 0) {
            s -= 1;
            list.setSelectedIndex(s);
            list.ensureIndexIsVisible(s);
        }
    }


    
Selected the previous row and force it to be visible.
See Also:
ensureIndexIsVisible.ensureIndexIsVisible/**
     * Selected the previous row and force it to be visible.
     *
     * @see JList#ensureIndexIsVisible
     */
    protected void selectNextIndex()
    {
        int s = list.getSelectedIndex();
        if((s + 1) < list.getModel().getSize()) {
            s += 1;
            list.setSelectedIndex(s);
            list.ensureIndexIsVisible(s);
        }
    }


    
Registers the keyboard bindings on the JList that the
BasicListUI is associated with. This method is called at
installUI() time.
See Also:
installUI/**
     * Registers the keyboard bindings on the <code>JList</code> that the
     * <code>BasicListUI</code> is associated with. This method is called at
     * installUI() time.
     *
     * @see #installUI
     */
    protected void installKeyboardActions() {
        InputMap inputMap = getInputMap(JComponent.WHEN_FOCUSED);

        SwingUtilities.replaceUIInputMap(list, JComponent.WHEN_FOCUSED,
                                           inputMap);

        LazyActionMap.installLazyActionMap(list, BasicListUI.class,
                                           "List.actionMap");
    }

    InputMap getInputMap(int condition) {
        if (condition == JComponent.WHEN_FOCUSED) {
            InputMap keyMap = (InputMap)DefaultLookup.get(
                             list, this, "List.focusInputMap");
            InputMap rtlKeyMap;

            if (isLeftToRight ||
                ((rtlKeyMap = (InputMap)DefaultLookup.get(list, this,
                              "List.focusInputMap.RightToLeft")) == null)) {
                    return keyMap;
            } else {
                rtlKeyMap.setParent(keyMap);
                return rtlKeyMap;
            }
        }
        return null;
    }

    
Unregisters keyboard actions installed from
installKeyboardActions.
This method is called at uninstallUI() time - subclassess should
ensure that all of the keyboard actions registered at installUI
time are removed here.
See Also:
installUI/**
     * Unregisters keyboard actions installed from
     * <code>installKeyboardActions</code>.
     * This method is called at uninstallUI() time - subclassess should
     * ensure that all of the keyboard actions registered at installUI
     * time are removed here.
     *
     * @see #installUI
     */
    protected void uninstallKeyboardActions() {
        SwingUtilities.replaceUIActionMap(list, null);
        SwingUtilities.replaceUIInputMap(list, JComponent.WHEN_FOCUSED, null);
    }


    
Creates and installs the listeners for the JList, its model, and its
selectionModel.  This method is called at installUI() time.
See Also:
installUI
uninstallListeners/**
     * Creates and installs the listeners for the JList, its model, and its
     * selectionModel.  This method is called at installUI() time.
     *
     * @see #installUI
     * @see #uninstallListeners
     */
    protected void installListeners()
    {
        TransferHandler th = list.getTransferHandler();
        if (th == null || th instanceof UIResource) {
            list.setTransferHandler(defaultTransferHandler);
            // default TransferHandler doesn't support drop
            // so we don't want drop handling
            if (list.getDropTarget() instanceof UIResource) {
                list.setDropTarget(null);
            }
        }

        focusListener = createFocusListener();
        mouseInputListener = createMouseInputListener();
        propertyChangeListener = createPropertyChangeListener();
        listSelectionListener = createListSelectionListener();
        listDataListener = createListDataListener();

        list.addFocusListener(focusListener);
        list.addMouseListener(mouseInputListener);
        list.addMouseMotionListener(mouseInputListener);
        list.addPropertyChangeListener(propertyChangeListener);
        list.addKeyListener(getHandler());

        ListModel<Object> model = list.getModel();
        if (model != null) {
            model.addListDataListener(listDataListener);
        }

        ListSelectionModel selectionModel = list.getSelectionModel();
        if (selectionModel != null) {
            selectionModel.addListSelectionListener(listSelectionListener);
        }
    }


    
Removes the listeners from the JList, its model, and its
selectionModel.  All of the listener fields, are reset to
null here.  This method is called at uninstallUI() time,
it should be kept in sync with installListeners.
See Also:
uninstallUI
installListeners/**
     * Removes the listeners from the JList, its model, and its
     * selectionModel.  All of the listener fields, are reset to
     * null here.  This method is called at uninstallUI() time,
     * it should be kept in sync with installListeners.
     *
     * @see #uninstallUI
     * @see #installListeners
     */
    protected void uninstallListeners()
    {
        list.removeFocusListener(focusListener);
        list.removeMouseListener(mouseInputListener);
        list.removeMouseMotionListener(mouseInputListener);
        list.removePropertyChangeListener(propertyChangeListener);
        list.removeKeyListener(getHandler());

        ListModel<Object> model = list.getModel();
        if (model != null) {
            model.removeListDataListener(listDataListener);
        }

        ListSelectionModel selectionModel = list.getSelectionModel();
        if (selectionModel != null) {
            selectionModel.removeListSelectionListener(listSelectionListener);
        }

        focusListener = null;
        mouseInputListener  = null;
        listSelectionListener = null;
        listDataListener = null;
        propertyChangeListener = null;
        handler = null;
    }


    
Initializes list properties such as font, foreground, and background,
and adds the CellRendererPane. The font, foreground, and background
properties are only set if their current value is either null
or a UIResource, other properties are set if the current
value is null.
See Also:
uninstallDefaults
installUI
CellRendererPane/**
     * Initializes list properties such as font, foreground, and background,
     * and adds the CellRendererPane. The font, foreground, and background
     * properties are only set if their current value is either null
     * or a UIResource, other properties are set if the current
     * value is null.
     *
     * @see #uninstallDefaults
     * @see #installUI
     * @see CellRendererPane
     */
    protected void installDefaults()
    {
        list.setLayout(null);

        LookAndFeel.installBorder(list, "List.border");

        LookAndFeel.installColorsAndFont(list, "List.background", "List.foreground", "List.font");

        LookAndFeel.installProperty(list, "opaque", Boolean.TRUE);

        if (list.getCellRenderer() == null) {
            @SuppressWarnings("unchecked")
            ListCellRenderer<Object> tmp = (ListCellRenderer)(UIManager.get("List.cellRenderer"));
            list.setCellRenderer(tmp);
        }

        Color sbg = list.getSelectionBackground();
        if (sbg == null || sbg instanceof UIResource) {
            list.setSelectionBackground(UIManager.getColor("List.selectionBackground"));
        }

        Color sfg = list.getSelectionForeground();
        if (sfg == null || sfg instanceof UIResource) {
            list.setSelectionForeground(UIManager.getColor("List.selectionForeground"));
        }

        Long l = (Long)UIManager.get("List.timeFactor");
        timeFactor = (l!=null) ? l.longValue() : 1000L;

        updateIsFileList();
    }

    private void updateIsFileList() {
        boolean b = Boolean.TRUE.equals(list.getClientProperty("List.isFileList"));
        if (b != isFileList) {
            isFileList = b;
            Font oldFont = list.getFont();
            if (oldFont == null || oldFont instanceof UIResource) {
                Font newFont = UIManager.getFont(b ? "FileChooser.listFont" : "List.font");
                if (newFont != null && newFont != oldFont) {
                    list.setFont(newFont);
                }
            }
        }
    }


    
Sets the list properties that have not been explicitly overridden to null. A property is considered overridden if its current value is not a UIResource. 
See Also:
installDefaults
uninstallUI
CellRendererPane/**
     * Sets the list properties that have not been explicitly overridden to
     * {@code null}. A property is considered overridden if its current value
     * is not a {@code UIResource}.
     *
     * @see #installDefaults
     * @see #uninstallUI
     * @see CellRendererPane
     */
    protected void uninstallDefaults()
    {
        LookAndFeel.uninstallBorder(list);
        if (list.getFont() instanceof UIResource) {
            list.setFont(null);
        }
        if (list.getForeground() instanceof UIResource) {
            list.setForeground(null);
        }
        if (list.getBackground() instanceof UIResource) {
            list.setBackground(null);
        }
        if (list.getSelectionBackground() instanceof UIResource) {
            list.setSelectionBackground(null);
        }
        if (list.getSelectionForeground() instanceof UIResource) {
            list.setSelectionForeground(null);
        }
        if (list.getCellRenderer() instanceof UIResource) {
            list.setCellRenderer(null);
        }
        if (list.getTransferHandler() instanceof UIResource) {
            list.setTransferHandler(null);
        }
    }


    
Initializes this.list by calling installDefaults(),
installListeners(), and installKeyboardActions()
in order.
See Also:
installDefaults
installListeners
installKeyboardActions/**
     * Initializes <code>this.list</code> by calling <code>installDefaults()</code>,
     * <code>installListeners()</code>, and <code>installKeyboardActions()</code>
     * in order.
     *
     * @see #installDefaults
     * @see #installListeners
     * @see #installKeyboardActions
     */
    public void installUI(JComponent c)
    {
        @SuppressWarnings("unchecked")
        JList<Object> tmp = (JList)c;
        list = tmp;

        layoutOrientation = list.getLayoutOrientation();

        rendererPane = new CellRendererPane();
        list.add(rendererPane);

        columnCount = 1;

        updateLayoutStateNeeded = modelChanged;
        isLeftToRight = list.getComponentOrientation().isLeftToRight();

        installDefaults();
        installListeners();
        installKeyboardActions();
    }


    
Uninitializes this.list by calling uninstallListeners(),
uninstallKeyboardActions(), and uninstallDefaults()
in order.  Sets this.list to null.
See Also:
uninstallListeners
uninstallKeyboardActions
uninstallDefaults/**
     * Uninitializes <code>this.list</code> by calling <code>uninstallListeners()</code>,
     * <code>uninstallKeyboardActions()</code>, and <code>uninstallDefaults()</code>
     * in order.  Sets this.list to null.
     *
     * @see #uninstallListeners
     * @see #uninstallKeyboardActions
     * @see #uninstallDefaults
     */
    public void uninstallUI(JComponent c)
    {
        uninstallListeners();
        uninstallDefaults();
        uninstallKeyboardActions();

        cellWidth = cellHeight = -1;
        cellHeights = null;

        listWidth = listHeight = -1;

        list.remove(rendererPane);
        rendererPane = null;
        list = null;
    }


    
Returns a new instance of BasicListUI. BasicListUI delegates are allocated one per JList. 
Params:
list – a component
Returns:
a new ListUI implementation for the Windows look and feel./**
     * Returns a new instance of {@code BasicListUI}.
     * {@code BasicListUI} delegates are allocated one per {@code JList}.
     *
     * @param list a component
     * @return a new {@code ListUI} implementation for the Windows look and feel.
     */
    public static ComponentUI createUI(JComponent list) {
        return new BasicListUI();
    }


    
{@inheritDoc}
Throws:
NullPointerException – {@inheritDoc}/**
     * {@inheritDoc}
     * @throws NullPointerException {@inheritDoc}
     */
    public int locationToIndex(JList<?> list, Point location) {
        maybeUpdateLayoutState();
        return convertLocationToModel(location.x, location.y);
    }


    
{@inheritDoc}
/**
     * {@inheritDoc}
     */
    public Point indexToLocation(JList<?> list, int index) {
        maybeUpdateLayoutState();
        Rectangle rect = getCellBounds(list, index, index);

        if (rect != null) {
            return new Point(rect.x, rect.y);
        }
        return null;
    }


    
{@inheritDoc}
/**
     * {@inheritDoc}
     */
    public Rectangle getCellBounds(JList<?> list, int index1, int index2) {
        maybeUpdateLayoutState();

        int minIndex = Math.min(index1, index2);
        int maxIndex = Math.max(index1, index2);

        if (minIndex >= list.getModel().getSize()) {
            return null;
        }

        Rectangle minBounds = getCellBounds(list, minIndex);

        if (minBounds == null) {
            return null;
        }
        if (minIndex == maxIndex) {
            return minBounds;
        }
        Rectangle maxBounds = getCellBounds(list, maxIndex);

        if (maxBounds != null) {
            if (layoutOrientation == JList.HORIZONTAL_WRAP) {
                int minRow = convertModelToRow(minIndex);
                int maxRow = convertModelToRow(maxIndex);

                if (minRow != maxRow) {
                    minBounds.x = 0;
                    minBounds.width = list.getWidth();
                }
            }
            else if (minBounds.x != maxBounds.x) {
                // Different columns
                minBounds.y = 0;
                minBounds.height = list.getHeight();
            }
            minBounds.add(maxBounds);
        }
        return minBounds;
    }

    
Gets the bounds of the specified model index, returning the resulting
bounds, or null if index is not valid.
/**
     * Gets the bounds of the specified model index, returning the resulting
     * bounds, or null if <code>index</code> is not valid.
     */
    private Rectangle getCellBounds(JList<?> list, int index) {
        maybeUpdateLayoutState();

        int row = convertModelToRow(index);
        int column = convertModelToColumn(index);

        if (row == -1 || column == -1) {
            return null;
        }

        Insets insets = list.getInsets();
        int x;
        int w = cellWidth;
        int y = insets.top;
        int h;
        switch (layoutOrientation) {
        case JList.VERTICAL_WRAP:
        case JList.HORIZONTAL_WRAP:
            if (isLeftToRight) {
                x = insets.left + column * cellWidth;
            } else {
                x = list.getWidth() - insets.right - (column+1) * cellWidth;
            }
            y += cellHeight * row;
            h = cellHeight;
            break;
        default:
            x = insets.left;
            if (cellHeights == null) {
                y += (cellHeight * row);
            }
            else if (row >= cellHeights.length) {
                y = 0;
            }
            else {
                for(int i = 0; i < row; i++) {
                    y += cellHeights[i];
                }
            }
            w = list.getWidth() - (insets.left + insets.right);
            h = getRowHeight(index);
            break;
        }
        return new Rectangle(x, y, w, h);
    }

    
Returns the height of the specified row based on the current layout.
Params:
row – a row
See Also:
convertYToRow
convertRowToY
updateLayoutState
Returns:
the specified row height or -1 if row isn't valid/**
     * Returns the height of the specified row based on the current layout.
     *
     * @param row a row
     * @return the specified row height or -1 if row isn't valid
     * @see #convertYToRow
     * @see #convertRowToY
     * @see #updateLayoutState
     */
    protected int getRowHeight(int row)
    {
        return getHeight(0, row);
    }


    
Convert the JList relative coordinate to the row that contains it, based on the current layout. If y0 doesn't fall within any row, return -1. 
Params:
y0 – a relative Y coordinate
See Also:
getRowHeight
updateLayoutState
Returns:
the row that contains y0, or -1/**
     * Convert the {@code JList} relative coordinate to the row that contains it,
     * based on the current layout. If {@code y0} doesn't fall within any row,
     * return -1.
     *
     * @param y0 a relative Y coordinate
     * @return the row that contains y0, or -1
     * @see #getRowHeight
     * @see #updateLayoutState
     */
    protected int convertYToRow(int y0)
    {
        return convertLocationToRow(0, y0, false);
    }


    
Return the JList relative Y coordinate of the origin of the specified row or -1 if row isn't valid. 
Params:
row – a row
See Also:
getRowHeight
updateLayoutState
Returns:
the Y coordinate of the origin of row, or -1/**
     * Return the {@code JList} relative Y coordinate of the origin of the specified
     * row or -1 if row isn't valid.
     *
     * @param row a row
     * @return the Y coordinate of the origin of row, or -1
     * @see #getRowHeight
     * @see #updateLayoutState
     */
    protected int convertRowToY(int row)
    {
        if (row >= getRowCount(0) || row < 0) {
            return -1;
        }
        Rectangle bounds = getCellBounds(list, row, row);
        return bounds.y;
    }

    
Returns the height of the cell at the passed in location.
/**
     * Returns the height of the cell at the passed in location.
     */
    private int getHeight(int column, int row) {
        if (column < 0 || column > columnCount || row < 0) {
            return -1;
        }
        if (layoutOrientation != JList.VERTICAL) {
            return cellHeight;
        }
        if (row >= list.getModel().getSize()) {
            return -1;
        }
        return (cellHeights == null) ? cellHeight :
                           ((row < cellHeights.length) ? cellHeights[row] : -1);
    }

    
Returns the row at location x/y.
Params:
closest – If true and the location doesn't exactly match a
               particular location, this will return the closest row./**
     * Returns the row at location x/y.
     *
     * @param closest If true and the location doesn't exactly match a
     *                particular location, this will return the closest row.
     */
    private int convertLocationToRow(int x, int y0, boolean closest) {
        int size = list.getModel().getSize();

        if (size <= 0) {
            return -1;
        }
        Insets insets = list.getInsets();
        if (cellHeights == null) {
            int row = (cellHeight == 0) ? 0 :
                           ((y0 - insets.top) / cellHeight);
            if (closest) {
                if (row < 0) {
                    row = 0;
                }
                else if (row >= size) {
                    row = size - 1;
                }
            }
            return row;
        }
        else if (size > cellHeights.length) {
            return -1;
        }
        else {
            int y = insets.top;
            int row = 0;

            if (closest && y0 < y) {
                return 0;
            }
            int i;
            for (i = 0; i < size; i++) {
                if ((y0 >= y) && (y0 < y + cellHeights[i])) {
                    return row;
                }
                y += cellHeights[i];
                row += 1;
            }
            return i - 1;
        }
    }

    
Returns the closest row that starts at the specified y-location
in the passed in column.
/**
     * Returns the closest row that starts at the specified y-location
     * in the passed in column.
     */
    private int convertLocationToRowInColumn(int y, int column) {
        int x = 0;

        if (layoutOrientation != JList.VERTICAL) {
            if (isLeftToRight) {
                x = column * cellWidth;
            } else {
                x = list.getWidth() - (column+1)*cellWidth - list.getInsets().right;
            }
        }
        return convertLocationToRow(x, y, true);
    }

    
Returns the closest location to the model index of the passed in
location.
/**
     * Returns the closest location to the model index of the passed in
     * location.
     */
    private int convertLocationToModel(int x, int y) {
        int row = convertLocationToRow(x, y, true);
        int column = convertLocationToColumn(x, y);

        if (row >= 0 && column >= 0) {
            return getModelIndex(column, row);
        }
        return -1;
    }

    
Returns the number of rows in the given column.
/**
     * Returns the number of rows in the given column.
     */
    private int getRowCount(int column) {
        if (column < 0 || column >= columnCount) {
            return -1;
        }
        if (layoutOrientation == JList.VERTICAL ||
                  (column == 0 && columnCount == 1)) {
            return list.getModel().getSize();
        }
        if (column >= columnCount) {
            return -1;
        }
        if (layoutOrientation == JList.VERTICAL_WRAP) {
            if (column < (columnCount - 1)) {
                return rowsPerColumn;
            }
            return list.getModel().getSize() - (columnCount - 1) *
                        rowsPerColumn;
        }
        // JList.HORIZONTAL_WRAP
        int diff = columnCount - (columnCount * rowsPerColumn -
                                  list.getModel().getSize());

        if (column >= diff) {
            return Math.max(0, rowsPerColumn - 1);
        }
        return rowsPerColumn;
    }

    
Returns the model index for the specified display location.
If columnxrow is beyond the length of the
model, this will return the model size - 1.
/**
     * Returns the model index for the specified display location.
     * If <code>column</code>x<code>row</code> is beyond the length of the
     * model, this will return the model size - 1.
     */
    private int getModelIndex(int column, int row) {
        switch (layoutOrientation) {
        case JList.VERTICAL_WRAP:
            return Math.min(list.getModel().getSize() - 1, rowsPerColumn *
                            column + Math.min(row, rowsPerColumn-1));
        case JList.HORIZONTAL_WRAP:
            return Math.min(list.getModel().getSize() - 1, row * columnCount +
                            column);
        default:
            return row;
        }
    }

    
Returns the closest column to the passed in location.
/**
     * Returns the closest column to the passed in location.
     */
    private int convertLocationToColumn(int x, int y) {
        if (cellWidth > 0) {
            if (layoutOrientation == JList.VERTICAL) {
                return 0;
            }
            Insets insets = list.getInsets();
            int col;
            if (isLeftToRight) {
                col = (x - insets.left) / cellWidth;
            } else {
                col = (list.getWidth() - x - insets.right - 1) / cellWidth;
            }
            if (col < 0) {
                return 0;
            }
            else if (col >= columnCount) {
                return columnCount - 1;
            }
            return col;
        }
        return 0;
    }

    
Returns the row that the model index index will be
displayed in..
/**
     * Returns the row that the model index <code>index</code> will be
     * displayed in..
     */
    private int convertModelToRow(int index) {
        int size = list.getModel().getSize();

        if ((index < 0) || (index >= size)) {
            return -1;
        }

        if (layoutOrientation != JList.VERTICAL && columnCount > 1 &&
                                                   rowsPerColumn > 0) {
            if (layoutOrientation == JList.VERTICAL_WRAP) {
                return index % rowsPerColumn;
            }
            return index / columnCount;
        }
        return index;
    }

    
Returns the column that the model index index will be
displayed in.
/**
     * Returns the column that the model index <code>index</code> will be
     * displayed in.
     */
    private int convertModelToColumn(int index) {
        int size = list.getModel().getSize();

        if ((index < 0) || (index >= size)) {
            return -1;
        }

        if (layoutOrientation != JList.VERTICAL && rowsPerColumn > 0 &&
                                                   columnCount > 1) {
            if (layoutOrientation == JList.VERTICAL_WRAP) {
                return index / rowsPerColumn;
            }
            return index % columnCount;
        }
        return 0;
    }

    
If updateLayoutStateNeeded is non zero, call updateLayoutState() and reset
updateLayoutStateNeeded.  This method should be called by methods
before doing any computation based on the geometry of the list.
For example it's the first call in paint() and getPreferredSize().
See Also:
updateLayoutState/**
     * If updateLayoutStateNeeded is non zero, call updateLayoutState() and reset
     * updateLayoutStateNeeded.  This method should be called by methods
     * before doing any computation based on the geometry of the list.
     * For example it's the first call in paint() and getPreferredSize().
     *
     * @see #updateLayoutState
     */
    protected void maybeUpdateLayoutState()
    {
        if (updateLayoutStateNeeded != 0) {
            updateLayoutState();
            updateLayoutStateNeeded = 0;
        }
    }


    
Recompute the value of cellHeight or cellHeights based
and cellWidth, based on the current font and the current
values of fixedCellWidth, fixedCellHeight, and prototypeCellValue.
See Also:
maybeUpdateLayoutState/**
     * Recompute the value of cellHeight or cellHeights based
     * and cellWidth, based on the current font and the current
     * values of fixedCellWidth, fixedCellHeight, and prototypeCellValue.
     *
     * @see #maybeUpdateLayoutState
     */
    protected void updateLayoutState()
    {
        /* If both JList fixedCellWidth and fixedCellHeight have been
         * set, then initialize cellWidth and cellHeight, and set
         * cellHeights to null.
         */

        int fixedCellHeight = list.getFixedCellHeight();
        int fixedCellWidth = list.getFixedCellWidth();

        cellWidth = (fixedCellWidth != -1) ? fixedCellWidth : -1;

        if (fixedCellHeight != -1) {
            cellHeight = fixedCellHeight;
            cellHeights = null;
        }
        else {
            cellHeight = -1;
            cellHeights = new int[list.getModel().getSize()];
        }

        /* If either of  JList fixedCellWidth and fixedCellHeight haven't
         * been set, then initialize cellWidth and cellHeights by
         * scanning through the entire model.  Note: if the renderer is
         * null, we just set cellWidth and cellHeights[*] to zero,
         * if they're not set already.
         */

        if ((fixedCellWidth == -1) || (fixedCellHeight == -1)) {

            ListModel<Object> dataModel = list.getModel();
            int dataModelSize = dataModel.getSize();
            ListCellRenderer<Object> renderer = list.getCellRenderer();

            if (renderer != null) {
                for(int index = 0; index < dataModelSize; index++) {
                    Object value = dataModel.getElementAt(index);
                    Component c = renderer.getListCellRendererComponent(list, value, index, false, false);
                    rendererPane.add(c);
                    Dimension cellSize = c.getPreferredSize();
                    if (fixedCellWidth == -1) {
                        cellWidth = Math.max(cellSize.width, cellWidth);
                    }
                    if (fixedCellHeight == -1) {
                        cellHeights[index] = cellSize.height;
                    }
                }
            }
            else {
                if (cellWidth == -1) {
                    cellWidth = 0;
                }
                if (cellHeights == null) {
                    cellHeights = new int[dataModelSize];
                }
                for(int index = 0; index < dataModelSize; index++) {
                    cellHeights[index] = 0;
                }
            }
        }

        columnCount = 1;
        if (layoutOrientation != JList.VERTICAL) {
            updateHorizontalLayoutState(fixedCellWidth, fixedCellHeight);
        }
    }

    
Invoked when the list is layed out horizontally to determine how
many columns to create.

This updates the rowsPerColumn, columnCount,
preferredHeight and potentially cellHeight
instance variables.
/**
     * Invoked when the list is layed out horizontally to determine how
     * many columns to create.
     * <p>
     * This updates the <code>rowsPerColumn, </code><code>columnCount</code>,
     * <code>preferredHeight</code> and potentially <code>cellHeight</code>
     * instance variables.
     */
    private void updateHorizontalLayoutState(int fixedCellWidth,
                                             int fixedCellHeight) {
        int visRows = list.getVisibleRowCount();
        int dataModelSize = list.getModel().getSize();
        Insets insets = list.getInsets();

        listHeight = list.getHeight();
        listWidth = list.getWidth();

        if (dataModelSize == 0) {
            rowsPerColumn = columnCount = 0;
            preferredHeight = insets.top + insets.bottom;
            return;
        }

        int height;

        if (fixedCellHeight != -1) {
            height = fixedCellHeight;
        }
        else {
            // Determine the max of the renderer heights.
            int maxHeight = 0;
            if (cellHeights.length > 0) {
                maxHeight = cellHeights[cellHeights.length - 1];
                for (int counter = cellHeights.length - 2;
                     counter >= 0; counter--) {
                    maxHeight = Math.max(maxHeight, cellHeights[counter]);
                }
            }
            height = cellHeight = maxHeight;
            cellHeights = null;
        }
        // The number of rows is either determined by the visible row
        // count, or by the height of the list.
        rowsPerColumn = dataModelSize;
        if (visRows > 0) {
            rowsPerColumn = visRows;
            columnCount = Math.max(1, dataModelSize / rowsPerColumn);
            if (dataModelSize > 0 && dataModelSize > rowsPerColumn &&
                dataModelSize % rowsPerColumn != 0) {
                columnCount++;
            }
            if (layoutOrientation == JList.HORIZONTAL_WRAP) {
                // Because HORIZONTAL_WRAP flows differently, the
                // rowsPerColumn needs to be adjusted.
                rowsPerColumn = (dataModelSize / columnCount);
                if (dataModelSize % columnCount > 0) {
                    rowsPerColumn++;
                }
            }
        }
        else if (layoutOrientation == JList.VERTICAL_WRAP && height != 0) {
            rowsPerColumn = Math.max(1, (listHeight - insets.top -
                                         insets.bottom) / height);
            columnCount = Math.max(1, dataModelSize / rowsPerColumn);
            if (dataModelSize > 0 && dataModelSize > rowsPerColumn &&
                dataModelSize % rowsPerColumn != 0) {
                columnCount++;
            }
        }
        else if (layoutOrientation == JList.HORIZONTAL_WRAP && cellWidth > 0 &&
                 listWidth > 0) {
            columnCount = Math.max(1, (listWidth - insets.left -
                                       insets.right) / cellWidth);
            rowsPerColumn = dataModelSize / columnCount;
            if (dataModelSize % columnCount > 0) {
                rowsPerColumn++;
            }
        }
        preferredHeight = rowsPerColumn * cellHeight + insets.top +
                              insets.bottom;
    }

    private Handler getHandler() {
        if (handler == null) {
            handler = new Handler();
        }
        return handler;
    }

    
Mouse input, and focus handling for JList.  An instance of this
class is added to the appropriate java.awt.Component lists
at installUI() time.  Note keyboard input is handled with JComponent
KeyboardActions, see installKeyboardActions().

Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans
has been added to the java.beans package. Please see XMLEncoder. 
See Also:
BasicListUI.createMouseInputListener
BasicListUI.installKeyboardActions
installUI/**
     * Mouse input, and focus handling for JList.  An instance of this
     * class is added to the appropriate java.awt.Component lists
     * at installUI() time.  Note keyboard input is handled with JComponent
     * KeyboardActions, see installKeyboardActions().
     * <p>
     * <strong>Warning:</strong>
     * Serialized objects of this class will not be compatible with
     * future Swing releases. The current serialization support is
     * appropriate for short term storage or RMI between applications running
     * the same version of Swing.  As of 1.4, support for long term storage
     * of all JavaBeans
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     *
     * @see #createMouseInputListener
     * @see #installKeyboardActions
     * @see #installUI
     */
    @SuppressWarnings("serial") // Same-version serialization only
    public class MouseInputHandler implements MouseInputListener
    {
        public void mouseClicked(MouseEvent e) {
            getHandler().mouseClicked(e);
        }

        public void mouseEntered(MouseEvent e) {
            getHandler().mouseEntered(e);
        }

        public void mouseExited(MouseEvent e) {
            getHandler().mouseExited(e);
        }

        public void mousePressed(MouseEvent e) {
            getHandler().mousePressed(e);
        }

        public void mouseDragged(MouseEvent e) {
            getHandler().mouseDragged(e);
        }

        public void mouseMoved(MouseEvent e) {
            getHandler().mouseMoved(e);
        }

        public void mouseReleased(MouseEvent e) {
            getHandler().mouseReleased(e);
        }
    }


    
Creates a delegate that implements MouseInputListener. The delegate is added to the corresponding java.awt.Component listener lists at installUI() time. Subclasses can override this method to return a custom MouseInputListener, e.g. 
class MyListUI extends BasicListUI {
   protected MouseInputListener createMouseInputListener() {
       return new MyMouseInputHandler();
   }
   public class MyMouseInputHandler extends MouseInputHandler {
       public void mouseMoved(MouseEvent e) {
           // do some extra work when the mouse moves
           super.mouseMoved(e);
       }
   }
}

See Also:
MouseInputHandler
installUI
Returns:
an instance of MouseInputListener/**
     * Creates a delegate that implements {@code MouseInputListener}.
     * The delegate is added to the corresponding {@code java.awt.Component} listener
     * lists at {@code installUI()} time. Subclasses can override this method to return
     * a custom {@code MouseInputListener}, e.g.
     * <pre>
     * class MyListUI extends BasicListUI {
     *    protected MouseInputListener <b>createMouseInputListener</b>() {
     *        return new MyMouseInputHandler();
     *    }
     *    public class MyMouseInputHandler extends MouseInputHandler {
     *        public void mouseMoved(MouseEvent e) {
     *            // do some extra work when the mouse moves
     *            super.mouseMoved(e);
     *        }
     *    }
     * }
     * </pre>
     *
     * @return an instance of {@code MouseInputListener}
     * @see MouseInputHandler
     * @see #installUI
     */
    protected MouseInputListener createMouseInputListener() {
        return getHandler();
    }

    
This class should be treated as a "protected" inner class. Instantiate it only within subclasses of BasicListUI. /**
     * This class should be treated as a &quot;protected&quot; inner class.
     * Instantiate it only within subclasses of {@code BasicListUI}.
     */
    public class FocusHandler implements FocusListener
    {
        
Repaints focused cells.
/**
         * Repaints focused cells.
         */
        protected void repaintCellFocus()
        {
            getHandler().repaintCellFocus();
        }

        /* The focusGained() focusLost() methods run when the JList
         * focus changes.
         */

        public void focusGained(FocusEvent e) {
            getHandler().focusGained(e);
        }

        public void focusLost(FocusEvent e) {
            getHandler().focusLost(e);
        }
    }

    
Returns an instance of FocusListener. 
Returns:
an instance of FocusListener/**
     * Returns an instance of {@code FocusListener}.
     *
     * @return an instance of {@code FocusListener}
     */
    protected FocusListener createFocusListener() {
        return getHandler();
    }

    
The ListSelectionListener that's added to the JLists selection
model at installUI time, and whenever the JList.selectionModel property
changes.  When the selection changes we repaint the affected rows.

Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans
has been added to the java.beans package. Please see XMLEncoder. 
See Also:
BasicListUI.createListSelectionListener
getCellBounds
installUI/**
     * The ListSelectionListener that's added to the JLists selection
     * model at installUI time, and whenever the JList.selectionModel property
     * changes.  When the selection changes we repaint the affected rows.
     * <p>
     * <strong>Warning:</strong>
     * Serialized objects of this class will not be compatible with
     * future Swing releases. The current serialization support is
     * appropriate for short term storage or RMI between applications running
     * the same version of Swing.  As of 1.4, support for long term storage
     * of all JavaBeans
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     *
     * @see #createListSelectionListener
     * @see #getCellBounds
     * @see #installUI
     */
    @SuppressWarnings("serial") // Same-version serialization only
    public class ListSelectionHandler implements ListSelectionListener
    {
        public void valueChanged(ListSelectionEvent e)
        {
            getHandler().valueChanged(e);
        }
    }


    
Creates an instance of ListSelectionHandler that's added to the JLists by selectionModel as needed. Subclasses can override this method to return a custom ListSelectionListener, e.g. 
class MyListUI extends BasicListUI {
   protected ListSelectionListener createListSelectionListener() {
       return new MySelectionListener();
   }
   public class MySelectionListener extends ListSelectionHandler {
       public void valueChanged(ListSelectionEvent e) {
           // do some extra work when the selection changes
           super.valueChange(e);
       }
   }
}

See Also:
ListSelectionHandler
installUI
Returns:
an instance of ListSelectionHandler/**
     * Creates an instance of {@code ListSelectionHandler} that's added to
     * the {@code JLists} by selectionModel as needed.  Subclasses can override
     * this method to return a custom {@code ListSelectionListener}, e.g.
     * <pre>
     * class MyListUI extends BasicListUI {
     *    protected ListSelectionListener <b>createListSelectionListener</b>() {
     *        return new MySelectionListener();
     *    }
     *    public class MySelectionListener extends ListSelectionHandler {
     *        public void valueChanged(ListSelectionEvent e) {
     *            // do some extra work when the selection changes
     *            super.valueChange(e);
     *        }
     *    }
     * }
     * </pre>
     *
     * @return an instance of {@code ListSelectionHandler}
     * @see ListSelectionHandler
     * @see #installUI
     */
    protected ListSelectionListener createListSelectionListener() {
        return getHandler();
    }


    private void redrawList() {
        list.revalidate();
        list.repaint();
    }


    
The ListDataListener that's added to the JLists model at installUI time, and whenever the JList.model property changes. 

Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans
has been added to the java.beans package. Please see XMLEncoder. 
See Also:
JList.getModel
BasicListUI.maybeUpdateLayoutState
BasicListUI.createListDataListener
installUI/**
     * The {@code ListDataListener} that's added to the {@code JLists} model at
     * {@code installUI time}, and whenever the JList.model property changes.
     * <p>
     * <strong>Warning:</strong>
     * Serialized objects of this class will not be compatible with
     * future Swing releases. The current serialization support is
     * appropriate for short term storage or RMI between applications running
     * the same version of Swing.  As of 1.4, support for long term storage
     * of all JavaBeans
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     *
     * @see JList#getModel
     * @see #maybeUpdateLayoutState
     * @see #createListDataListener
     * @see #installUI
     */
    @SuppressWarnings("serial") // Same-version serialization only
    public class ListDataHandler implements ListDataListener
    {
        public void intervalAdded(ListDataEvent e) {
            getHandler().intervalAdded(e);
        }


        public void intervalRemoved(ListDataEvent e)
        {
            getHandler().intervalRemoved(e);
        }


        public void contentsChanged(ListDataEvent e) {
            getHandler().contentsChanged(e);
        }
    }


    
Creates an instance of ListDataListener that's added to the JLists by model as needed. Subclasses can override this method to return a custom ListDataListener, e.g. 
class MyListUI extends BasicListUI {
   protected ListDataListener createListDataListener() {
       return new MyListDataListener();
   }
   public class MyListDataListener extends ListDataHandler {
       public void contentsChanged(ListDataEvent e) {
           // do some extra work when the models contents change
           super.contentsChange(e);
       }
   }
}

See Also:
ListDataListener
JList.getModel
installUI
Returns:
an instance of ListDataListener/**
     * Creates an instance of {@code ListDataListener} that's added to
     * the {@code JLists} by model as needed. Subclasses can override
     * this method to return a custom {@code ListDataListener}, e.g.
     * <pre>
     * class MyListUI extends BasicListUI {
     *    protected ListDataListener <b>createListDataListener</b>() {
     *        return new MyListDataListener();
     *    }
     *    public class MyListDataListener extends ListDataHandler {
     *        public void contentsChanged(ListDataEvent e) {
     *            // do some extra work when the models contents change
     *            super.contentsChange(e);
     *        }
     *    }
     * }
     * </pre>
     *
     * @return an instance of {@code ListDataListener}
     * @see ListDataListener
     * @see JList#getModel
     * @see #installUI
     */
    protected ListDataListener createListDataListener() {
        return getHandler();
    }


    
The PropertyChangeListener that's added to the JList at
installUI time.  When the value of a JList property that
affects layout changes, we set a bit in updateLayoutStateNeeded.
If the JLists model changes we additionally remove our listeners
from the old model.  Likewise for the JList selectionModel.

Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans
has been added to the java.beans package. Please see XMLEncoder. 
See Also:
BasicListUI.maybeUpdateLayoutState
BasicListUI.createPropertyChangeListener
installUI/**
     * The PropertyChangeListener that's added to the JList at
     * installUI time.  When the value of a JList property that
     * affects layout changes, we set a bit in updateLayoutStateNeeded.
     * If the JLists model changes we additionally remove our listeners
     * from the old model.  Likewise for the JList selectionModel.
     * <p>
     * <strong>Warning:</strong>
     * Serialized objects of this class will not be compatible with
     * future Swing releases. The current serialization support is
     * appropriate for short term storage or RMI between applications running
     * the same version of Swing.  As of 1.4, support for long term storage
     * of all JavaBeans
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     *
     * @see #maybeUpdateLayoutState
     * @see #createPropertyChangeListener
     * @see #installUI
     */
    @SuppressWarnings("serial") // Same-version serialization only
    public class PropertyChangeHandler implements PropertyChangeListener
    {
        public void propertyChange(PropertyChangeEvent e)
        {
            getHandler().propertyChange(e);
        }
    }


    
Creates an instance of PropertyChangeHandler that's added to the JList by installUI(). Subclasses can override this method to return a custom PropertyChangeListener, e.g. 
class MyListUI extends BasicListUI {
   protected PropertyChangeListener createPropertyChangeListener() {
       return new MyPropertyChangeListener();
   }
   public class MyPropertyChangeListener extends PropertyChangeHandler {
       public void propertyChange(PropertyChangeEvent e) {
           if (e.getPropertyName().equals("model")) {
               // do some extra work when the model changes
           }
           super.propertyChange(e);
       }
   }
}

See Also:
PropertyChangeListener
installUI
Returns:
an instance of PropertyChangeHandler/**
     * Creates an instance of {@code PropertyChangeHandler} that's added to
     * the {@code JList} by {@code installUI()}. Subclasses can override this method
     * to return a custom {@code PropertyChangeListener}, e.g.
     * <pre>
     * class MyListUI extends BasicListUI {
     *    protected PropertyChangeListener <b>createPropertyChangeListener</b>() {
     *        return new MyPropertyChangeListener();
     *    }
     *    public class MyPropertyChangeListener extends PropertyChangeHandler {
     *        public void propertyChange(PropertyChangeEvent e) {
     *            if (e.getPropertyName().equals("model")) {
     *                // do some extra work when the model changes
     *            }
     *            super.propertyChange(e);
     *        }
     *    }
     * }
     * </pre>
     *
     * @return an instance of {@code PropertyChangeHandler}
     * @see PropertyChangeListener
     * @see #installUI
     */
    protected PropertyChangeListener createPropertyChangeListener() {
        return getHandler();
    }

    
Used by IncrementLeadSelectionAction. Indicates the action should
change the lead, and not select it. /** Used by IncrementLeadSelectionAction. Indicates the action should
     * change the lead, and not select it. */
    private static final int CHANGE_LEAD = 0;
    
Used by IncrementLeadSelectionAction. Indicates the action should
change the selection and lead. /** Used by IncrementLeadSelectionAction. Indicates the action should
     * change the selection and lead. */
    private static final int CHANGE_SELECTION = 1;
    
Used by IncrementLeadSelectionAction. Indicates the action should
extend the selection from the anchor to the next index. /** Used by IncrementLeadSelectionAction. Indicates the action should
     * extend the selection from the anchor to the next index. */
    private static final int EXTEND_SELECTION = 2;


    private static class Actions extends UIAction {
        private static final String SELECT_PREVIOUS_COLUMN =
                                    "selectPreviousColumn";
        private static final String SELECT_PREVIOUS_COLUMN_EXTEND =
                                    "selectPreviousColumnExtendSelection";
        private static final String SELECT_PREVIOUS_COLUMN_CHANGE_LEAD =
                                    "selectPreviousColumnChangeLead";
        private static final String SELECT_NEXT_COLUMN = "selectNextColumn";
        private static final String SELECT_NEXT_COLUMN_EXTEND =
                                    "selectNextColumnExtendSelection";
        private static final String SELECT_NEXT_COLUMN_CHANGE_LEAD =
                                    "selectNextColumnChangeLead";
        private static final String SELECT_PREVIOUS_ROW = "selectPreviousRow";
        private static final String SELECT_PREVIOUS_ROW_EXTEND =
                                     "selectPreviousRowExtendSelection";
        private static final String SELECT_PREVIOUS_ROW_CHANGE_LEAD =
                                     "selectPreviousRowChangeLead";
        private static final String SELECT_NEXT_ROW = "selectNextRow";
        private static final String SELECT_NEXT_ROW_EXTEND =
                                     "selectNextRowExtendSelection";
        private static final String SELECT_NEXT_ROW_CHANGE_LEAD =
                                     "selectNextRowChangeLead";
        private static final String SELECT_FIRST_ROW = "selectFirstRow";
        private static final String SELECT_FIRST_ROW_EXTEND =
                                     "selectFirstRowExtendSelection";
        private static final String SELECT_FIRST_ROW_CHANGE_LEAD =
                                     "selectFirstRowChangeLead";
        private static final String SELECT_LAST_ROW = "selectLastRow";
        private static final String SELECT_LAST_ROW_EXTEND =
                                     "selectLastRowExtendSelection";
        private static final String SELECT_LAST_ROW_CHANGE_LEAD =
                                     "selectLastRowChangeLead";
        private static final String SCROLL_UP = "scrollUp";
        private static final String SCROLL_UP_EXTEND =
                                     "scrollUpExtendSelection";
        private static final String SCROLL_UP_CHANGE_LEAD =
                                     "scrollUpChangeLead";
        private static final String SCROLL_DOWN = "scrollDown";
        private static final String SCROLL_DOWN_EXTEND =
                                     "scrollDownExtendSelection";
        private static final String SCROLL_DOWN_CHANGE_LEAD =
                                     "scrollDownChangeLead";
        private static final String SELECT_ALL = "selectAll";
        private static final String CLEAR_SELECTION = "clearSelection";

        // add the lead item to the selection without changing lead or anchor
        private static final String ADD_TO_SELECTION = "addToSelection";

        // toggle the selected state of the lead item and move the anchor to it
        private static final String TOGGLE_AND_ANCHOR = "toggleAndAnchor";

        // extend the selection to the lead item
        private static final String EXTEND_TO = "extendTo";

        // move the anchor to the lead and ensure only that item is selected
        private static final String MOVE_SELECTION_TO = "moveSelectionTo";

        Actions(String name) {
            super(name);
        }
        public void actionPerformed(ActionEvent e) {
            String name = getName();
            @SuppressWarnings("unchecked")
            JList<Object> list = (JList)e.getSource();
            BasicListUI ui = (BasicListUI)BasicLookAndFeel.getUIOfType(
                     list.getUI(), BasicListUI.class);

            if (name == SELECT_PREVIOUS_COLUMN) {
                changeSelection(list, CHANGE_SELECTION,
                                getNextColumnIndex(list, ui, -1), -1);
            }
            else if (name == SELECT_PREVIOUS_COLUMN_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                getNextColumnIndex(list, ui, -1), -1);
            }
            else if (name == SELECT_PREVIOUS_COLUMN_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                getNextColumnIndex(list, ui, -1), -1);
            }
            else if (name == SELECT_NEXT_COLUMN) {
                changeSelection(list, CHANGE_SELECTION,
                                getNextColumnIndex(list, ui, 1), 1);
            }
            else if (name == SELECT_NEXT_COLUMN_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                getNextColumnIndex(list, ui, 1), 1);
            }
            else if (name == SELECT_NEXT_COLUMN_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                getNextColumnIndex(list, ui, 1), 1);
            }
            else if (name == SELECT_PREVIOUS_ROW) {
                changeSelection(list, CHANGE_SELECTION,
                                getNextIndex(list, ui, -1), -1);
            }
            else if (name == SELECT_PREVIOUS_ROW_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                getNextIndex(list, ui, -1), -1);
            }
            else if (name == SELECT_PREVIOUS_ROW_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                getNextIndex(list, ui, -1), -1);
            }
            else if (name == SELECT_NEXT_ROW) {
                changeSelection(list, CHANGE_SELECTION,
                                getNextIndex(list, ui, 1), 1);
            }
            else if (name == SELECT_NEXT_ROW_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                getNextIndex(list, ui, 1), 1);
            }
            else if (name == SELECT_NEXT_ROW_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                getNextIndex(list, ui, 1), 1);
            }
            else if (name == SELECT_FIRST_ROW) {
                changeSelection(list, CHANGE_SELECTION, 0, -1);
            }
            else if (name == SELECT_FIRST_ROW_EXTEND) {
                changeSelection(list, EXTEND_SELECTION, 0, -1);
            }
            else if (name == SELECT_FIRST_ROW_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD, 0, -1);
            }
            else if (name == SELECT_LAST_ROW) {
                changeSelection(list, CHANGE_SELECTION,
                                list.getModel().getSize() - 1, 1);
            }
            else if (name == SELECT_LAST_ROW_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                list.getModel().getSize() - 1, 1);
            }
            else if (name == SELECT_LAST_ROW_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                list.getModel().getSize() - 1, 1);
            }
            else if (name == SCROLL_UP) {
                changeSelection(list, CHANGE_SELECTION,
                                getNextPageIndex(list, -1), -1);
            }
            else if (name == SCROLL_UP_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                getNextPageIndex(list, -1), -1);
            }
            else if (name == SCROLL_UP_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                getNextPageIndex(list, -1), -1);
            }
            else if (name == SCROLL_DOWN) {
                changeSelection(list, CHANGE_SELECTION,
                                getNextPageIndex(list, 1), 1);
            }
            else if (name == SCROLL_DOWN_EXTEND) {
                changeSelection(list, EXTEND_SELECTION,
                                getNextPageIndex(list, 1), 1);
            }
            else if (name == SCROLL_DOWN_CHANGE_LEAD) {
                changeSelection(list, CHANGE_LEAD,
                                getNextPageIndex(list, 1), 1);
            }
            else if (name == SELECT_ALL) {
                selectAll(list);
            }
            else if (name == CLEAR_SELECTION) {
                clearSelection(list);
            }
            else if (name == ADD_TO_SELECTION) {
                int index = adjustIndex(
                    list.getSelectionModel().getLeadSelectionIndex(), list);

                if (!list.isSelectedIndex(index)) {
                    int oldAnchor = list.getSelectionModel().getAnchorSelectionIndex();
                    list.setValueIsAdjusting(true);
                    list.addSelectionInterval(index, index);
                    list.getSelectionModel().setAnchorSelectionIndex(oldAnchor);
                    list.setValueIsAdjusting(false);
                }
            }
            else if (name == TOGGLE_AND_ANCHOR) {
                int index = adjustIndex(
                    list.getSelectionModel().getLeadSelectionIndex(), list);

                if (list.isSelectedIndex(index)) {
                    list.removeSelectionInterval(index, index);
                } else {
                    list.addSelectionInterval(index, index);
                }
            }
            else if (name == EXTEND_TO) {
                changeSelection(
                    list, EXTEND_SELECTION,
                    adjustIndex(list.getSelectionModel().getLeadSelectionIndex(), list),
                    0);
            }
            else if (name == MOVE_SELECTION_TO) {
                changeSelection(
                    list, CHANGE_SELECTION,
                    adjustIndex(list.getSelectionModel().getLeadSelectionIndex(), list),
                    0);
            }
        }

        @Override
        public boolean accept(Object c) {
            Object name = getName();
            if (name == SELECT_PREVIOUS_COLUMN_CHANGE_LEAD ||
                    name == SELECT_NEXT_COLUMN_CHANGE_LEAD ||
                    name == SELECT_PREVIOUS_ROW_CHANGE_LEAD ||
                    name == SELECT_NEXT_ROW_CHANGE_LEAD ||
                    name == SELECT_FIRST_ROW_CHANGE_LEAD ||
                    name == SELECT_LAST_ROW_CHANGE_LEAD ||
                    name == SCROLL_UP_CHANGE_LEAD ||
                    name == SCROLL_DOWN_CHANGE_LEAD) {

                // discontinuous selection actions are only enabled for
                // DefaultListSelectionModel
                return c != null && ((JList)c).getSelectionModel()
                                        instanceof DefaultListSelectionModel;
            }

            return true;
        }

        private void clearSelection(JList<?> list) {
            list.clearSelection();
        }

        private void selectAll(JList<?> list) {
            int size = list.getModel().getSize();
            if (size > 0) {
                ListSelectionModel lsm = list.getSelectionModel();
                int lead = adjustIndex(lsm.getLeadSelectionIndex(), list);

                if (lsm.getSelectionMode() == ListSelectionModel.SINGLE_SELECTION) {
                    if (lead == -1) {
                        int min = adjustIndex(list.getMinSelectionIndex(), list);
                        lead = (min == -1 ? 0 : min);
                    }

                    list.setSelectionInterval(lead, lead);
                    list.ensureIndexIsVisible(lead);
                } else {
                    list.setValueIsAdjusting(true);

                    int anchor = adjustIndex(lsm.getAnchorSelectionIndex(), list);

                    list.setSelectionInterval(0, size - 1);

                    // this is done to restore the anchor and lead
                    SwingUtilities2.setLeadAnchorWithoutSelection(lsm, anchor, lead);

                    list.setValueIsAdjusting(false);
                }
            }
        }

        private int getNextPageIndex(JList<?> list, int direction) {
            if (list.getModel().getSize() == 0) {
                return -1;
            }

            int index = -1;
            Rectangle visRect = list.getVisibleRect();
            ListSelectionModel lsm = list.getSelectionModel();
            int lead = adjustIndex(lsm.getLeadSelectionIndex(), list);
            Rectangle leadRect =
                (lead==-1) ? new Rectangle() : list.getCellBounds(lead, lead);

            if (leadRect == null) {
                return index;
            }
            if (list.getLayoutOrientation() == JList.VERTICAL_WRAP &&
                    list.getVisibleRowCount() <= 0) {
                if (!list.getComponentOrientation().isLeftToRight()) {
                    direction = -direction;
                }
                // apply for horizontal scrolling: the step for next
                // page index is number of visible columns
                if (direction < 0) {
                    // left
                    visRect.x = leadRect.x + leadRect.width - visRect.width;
                    Point p = new Point(visRect.x - 1, leadRect.y);
                    index = list.locationToIndex(p);
                    if (index == -1) {
                        return index;
                    }
                    Rectangle cellBounds = list.getCellBounds(index, index);
                    if (cellBounds != null && visRect.intersects(cellBounds)) {
                        p.x = cellBounds.x - 1;
                        index = list.locationToIndex(p);
                        if (index == -1) {
                            return index;
                        }
                        cellBounds = list.getCellBounds(index, index);
                    }
                    // this is necessary for right-to-left orientation only
                    if (cellBounds != null && cellBounds.y != leadRect.y) {
                        p.x = cellBounds.x + cellBounds.width;
                        index = list.locationToIndex(p);
                    }
                }
                else {
                    // right
                    visRect.x = leadRect.x;
                    Point p = new Point(visRect.x + visRect.width, leadRect.y);
                    index = list.locationToIndex(p);
                    if (index == -1) {
                        return index;
                    }
                    Rectangle cellBounds = list.getCellBounds(index, index);
                    if (cellBounds != null && visRect.intersects(cellBounds)) {
                        p.x = cellBounds.x + cellBounds.width;
                        index = list.locationToIndex(p);
                        if (index == -1) {
                            return index;
                        }
                        cellBounds = list.getCellBounds(index, index);
                    }
                    if (cellBounds != null && cellBounds.y != leadRect.y) {
                        p.x = cellBounds.x - 1;
                        index = list.locationToIndex(p);
                    }
                }
            }
            else {
                if (direction < 0) {
                    // up
                    // go to the first visible cell
                    Point p = new Point(leadRect.x, visRect.y);
                    index = list.locationToIndex(p);
                    if (lead <= index) {
                        // if lead is the first visible cell (or above it)
                        // adjust the visible rect up
                        visRect.y = leadRect.y + leadRect.height - visRect.height;
                        p.y = visRect.y;
                        index = list.locationToIndex(p);
                        if (index == -1) {
                            return index;
                        }
                        Rectangle cellBounds = list.getCellBounds(index, index);
                        // go one cell down if first visible cell doesn't fit
                        // into adjasted visible rectangle
                        if (cellBounds != null && cellBounds.y < visRect.y) {
                            p.y = cellBounds.y + cellBounds.height;
                            index = list.locationToIndex(p);
                            if (index == -1) {
                                return index;
                            }
                            cellBounds = list.getCellBounds(index, index);
                        }
                        // if index isn't less then lead
                        // try to go to cell previous to lead
                        if (cellBounds != null && cellBounds.y >= leadRect.y) {
                            p.y = leadRect.y - 1;
                            index = list.locationToIndex(p);
                        }
                    }
                }
                else {
                    // down
                    // go to the last completely visible cell
                    Point p = new Point(leadRect.x,
                            visRect.y + visRect.height - 1);
                    index = list.locationToIndex(p);
                    if (index == -1) {
                        return index;
                    }
                    Rectangle cellBounds = list.getCellBounds(index, index);
                    // go up one cell if last visible cell doesn't fit
                    // into visible rectangle
                    if (cellBounds != null &&
                            cellBounds.y + cellBounds.height >
                            visRect.y + visRect.height)
                    {
                        p.y = cellBounds.y - 1;
                        index = list.locationToIndex(p);
                        if (index == -1) {
                            return index;
                        }
                        cellBounds = list.getCellBounds(index, index);
                        index = Math.max(index, lead);
                    }

                    if (lead >= index) {
                        // if lead is the last completely visible index
                        // (or below it) adjust the visible rect down
                        visRect.y = leadRect.y;
                        p.y = visRect.y + visRect.height - 1;
                        index = list.locationToIndex(p);
                        if (index == -1) {
                            return index;
                        }
                        cellBounds = list.getCellBounds(index, index);
                        // go one cell up if last visible cell doesn't fit
                        // into adjasted visible rectangle
                        if (cellBounds != null &&
                                cellBounds.y + cellBounds.height >
                                visRect.y + visRect.height)
                        {
                            p.y = cellBounds.y - 1;
                            index = list.locationToIndex(p);
                            if (index == -1) {
                                return index;
                            }
                            cellBounds = list.getCellBounds(index, index);
                        }
                        // if index isn't greater then lead
                        // try to go to cell next after lead
                        if (cellBounds != null && cellBounds.y <= leadRect.y) {
                            p.y = leadRect.y + leadRect.height;
                            index = list.locationToIndex(p);
                        }
                    }
                }
            }

            return index;
        }

        private void changeSelection(JList<?> list, int type,
                                     int index, int direction) {
            if (index >= 0 && index < list.getModel().getSize()) {
                ListSelectionModel lsm = list.getSelectionModel();

                // CHANGE_LEAD is only valid with multiple interval selection
                if (type == CHANGE_LEAD &&
                        list.getSelectionMode()
                            != ListSelectionModel.MULTIPLE_INTERVAL_SELECTION) {

                    type = CHANGE_SELECTION;
                }

                // IMPORTANT - This needs to happen before the index is changed.
                // This is because JFileChooser, which uses JList, also scrolls
                // the selected item into view. If that happens first, then
                // this method becomes a no-op.
                adjustScrollPositionIfNecessary(list, index, direction);

                if (type == EXTEND_SELECTION) {
                    int anchor = adjustIndex(lsm.getAnchorSelectionIndex(), list);
                    if (anchor == -1) {
                        anchor = 0;
                    }

                    list.setSelectionInterval(anchor, index);
                }
                else if (type == CHANGE_SELECTION) {
                    list.setSelectedIndex(index);
                }
                else {
                    // casting should be safe since the action is only enabled
                    // for DefaultListSelectionModel
                    ((DefaultListSelectionModel)lsm).moveLeadSelectionIndex(index);
                }
            }
        }

        
When scroll down makes selected index the last completely visible
index. When scroll up makes selected index the first visible index.
Adjust visible rectangle respect to list's component orientation.
/**
         * When scroll down makes selected index the last completely visible
         * index. When scroll up makes selected index the first visible index.
         * Adjust visible rectangle respect to list's component orientation.
         */
        private void adjustScrollPositionIfNecessary(JList<?> list, int index,
                                                     int direction) {
            if (direction == 0) {
                return;
            }
            Rectangle cellBounds = list.getCellBounds(index, index);
            Rectangle visRect = list.getVisibleRect();
            if (cellBounds != null && !visRect.contains(cellBounds)) {
                if (list.getLayoutOrientation() == JList.VERTICAL_WRAP &&
                    list.getVisibleRowCount() <= 0) {
                    // horizontal
                    if (list.getComponentOrientation().isLeftToRight()) {
                        if (direction > 0) {
                            // right for left-to-right
                            int x =Math.max(0,
                                cellBounds.x + cellBounds.width - visRect.width);
                            int startIndex =
                                list.locationToIndex(new Point(x, cellBounds.y));
                            if (startIndex == -1) {
                                return;
                            }
                            Rectangle startRect = list.getCellBounds(startIndex,
                                                                     startIndex);
                            if (startRect != null &&
                                startRect.x < x && startRect.x < cellBounds.x) {
                                startRect.x += startRect.width;
                                startIndex =
                                    list.locationToIndex(startRect.getLocation());
                                if (startIndex == -1) {
                                    return;
                                }
                                startRect = list.getCellBounds(startIndex,
                                                               startIndex);
                            }
                            cellBounds = startRect;
                        }
                        if (cellBounds != null) {
                            cellBounds.width = visRect.width;
                        }
                    }
                    else {
                        if (direction > 0) {
                            // left for right-to-left
                            int x = cellBounds.x + visRect.width;
                            int rightIndex =
                                list.locationToIndex(new Point(x, cellBounds.y));
                            if (rightIndex == -1) {
                                return;
                            }
                            Rectangle rightRect = list.getCellBounds(rightIndex,
                                                                     rightIndex);
                            if (rightRect != null) {
                                if (rightRect.x + rightRect.width > x &&
                                        rightRect.x > cellBounds.x) {
                                    rightRect.width = 0;
                                }
                                cellBounds.x = Math.max(0,
                                        rightRect.x + rightRect.width - visRect.width);
                                cellBounds.width = visRect.width;
                            }
                        }
                        else {
                            cellBounds.x += Math.max(0,
                                cellBounds.width - visRect.width);
                            // adjust width to fit into visible rectangle
                            cellBounds.width = Math.min(cellBounds.width,
                                                        visRect.width);
                        }
                    }
                }
                else {
                    // vertical
                    if (direction > 0 &&
                            (cellBounds.y < visRect.y ||
                                    cellBounds.y + cellBounds.height
                                            > visRect.y + visRect.height)) {
                        //down
                        int y = Math.max(0,
                            cellBounds.y + cellBounds.height - visRect.height);
                        int startIndex =
                            list.locationToIndex(new Point(cellBounds.x, y));
                        if (startIndex == -1) {
                            return;
                        }
                        Rectangle startRect = list.getCellBounds(startIndex,
                                                                 startIndex);
                        if (startRect != null &&
                                startRect.y < y && startRect.y < cellBounds.y) {
                            startRect.y += startRect.height;
                            startIndex =
                                list.locationToIndex(startRect.getLocation());
                            if (startIndex == -1) {
                                return;
                            }
                            startRect =
                                list.getCellBounds(startIndex, startIndex);
                        }
                        cellBounds = startRect;
                        if (cellBounds != null) {
                            cellBounds.height = visRect.height;
                        }
                    }
                    else {
                        // adjust height to fit into visible rectangle
                        cellBounds.height = Math.min(cellBounds.height, visRect.height);
                    }
                }
                if (cellBounds != null) {
                    list.scrollRectToVisible(cellBounds);
                }
            }
        }

        private int getNextColumnIndex(JList<?> list, BasicListUI ui,
                                       int amount) {
            if (list.getLayoutOrientation() != JList.VERTICAL) {
                int index = adjustIndex(list.getLeadSelectionIndex(), list);
                int size = list.getModel().getSize();

                if (index == -1) {
                    return 0;
                } else if (size == 1) {
                    // there's only one item so we should select it
                    return 0;
                } else if (ui == null || ui.columnCount <= 1) {
                    return -1;
                }

                int column = ui.convertModelToColumn(index);
                int row = ui.convertModelToRow(index);

                column += amount;
                if (column >= ui.columnCount || column < 0) {
                    // No wrapping.
                    return -1;
                }
                int maxRowCount = ui.getRowCount(column);
                if (row >= maxRowCount) {
                    return -1;
                }
                return ui.getModelIndex(column, row);
            }
            // Won't change the selection.
            return -1;
        }

        private int getNextIndex(JList<?> list, BasicListUI ui, int amount) {
            int index = adjustIndex(list.getLeadSelectionIndex(), list);
            int size = list.getModel().getSize();

            if (index == -1) {
                if (size > 0) {
                    if (amount > 0) {
                        index = 0;
                    }
                    else {
                        index = size - 1;
                    }
                }
            } else if (size == 1) {
                // there's only one item so we should select it
                index = 0;
            } else if (list.getLayoutOrientation() == JList.HORIZONTAL_WRAP) {
                if (ui != null) {
                    index += ui.columnCount * amount;
                }
            } else {
                index += amount;
            }

            return index;
        }
    }


    private class Handler implements FocusListener, KeyListener,
                          ListDataListener, ListSelectionListener,
                          MouseInputListener, PropertyChangeListener,
                          BeforeDrag {
        //
        // KeyListener
        //
        private String prefix = "";
        private String typedString = "";
        private long lastTime = 0L;

        
Invoked when a key has been typed.
Moves the keyboard focus to the first element whose prefix matches the
sequence of alphanumeric keys pressed by the user with delay less
than value of timeFactor property (or 1000 milliseconds
if it is not defined). Subsequent same key presses move the keyboard
focus to the next object that starts with the same letter until another
key is pressed, then it is treated as the prefix with appropriate number
of the same letters followed by first typed another letter.
/**
         * Invoked when a key has been typed.
         *
         * Moves the keyboard focus to the first element whose prefix matches the
         * sequence of alphanumeric keys pressed by the user with delay less
         * than value of <code>timeFactor</code> property (or 1000 milliseconds
         * if it is not defined). Subsequent same key presses move the keyboard
         * focus to the next object that starts with the same letter until another
         * key is pressed, then it is treated as the prefix with appropriate number
         * of the same letters followed by first typed another letter.
         */
        public void keyTyped(KeyEvent e) {
            JList<?> src = (JList)e.getSource();
            ListModel<?> model = src.getModel();

            if (model.getSize() == 0 || e.isAltDown() ||
                    BasicGraphicsUtils.isMenuShortcutKeyDown(e) ||
                    isNavigationKey(e)) {
                // Nothing to select
                return;
            }
            boolean startingFromSelection = true;

            char c = e.getKeyChar();

            long time = e.getWhen();
            int startIndex = adjustIndex(src.getLeadSelectionIndex(), list);
            if (time - lastTime < timeFactor) {
                typedString += c;
                if((prefix.length() == 1) && (c == prefix.charAt(0))) {
                    // Subsequent same key presses move the keyboard focus to the next
                    // object that starts with the same letter.
                    startIndex++;
                } else {
                    prefix = typedString;
                }
            } else {
                startIndex++;
                typedString = "" + c;
                prefix = typedString;
            }
            lastTime = time;

            if (startIndex < 0 || startIndex >= model.getSize()) {
                startingFromSelection = false;
                startIndex = 0;
            }
            int index = src.getNextMatch(prefix, startIndex,
                                         Position.Bias.Forward);
            if (index >= 0) {
                src.setSelectedIndex(index);
                src.ensureIndexIsVisible(index);
            } else if (startingFromSelection) { // wrap
                index = src.getNextMatch(prefix, 0,
                                         Position.Bias.Forward);
                if (index >= 0) {
                    src.setSelectedIndex(index);
                    src.ensureIndexIsVisible(index);
                }
            }
        }

        
Invoked when a key has been pressed.
Checks to see if the key event is a navigation key to prevent
dispatching these keys for the first letter navigation.
/**
         * Invoked when a key has been pressed.
         *
         * Checks to see if the key event is a navigation key to prevent
         * dispatching these keys for the first letter navigation.
         */
        public void keyPressed(KeyEvent e) {
            if ( isNavigationKey(e) ) {
                prefix = "";
                typedString = "";
                lastTime = 0L;
            }
        }

        
Invoked when a key has been released. See the class description for KeyEvent for a definition of a key released event. /**
         * Invoked when a key has been released.
         * See the class description for {@link KeyEvent} for a definition of
         * a key released event.
         */
        public void keyReleased(KeyEvent e) {
        }

        
Returns whether or not the supplied key event maps to a key that is used for
navigation.  This is used for optimizing key input by only passing non-
navigation keys to the first letter navigation mechanism.
/**
         * Returns whether or not the supplied key event maps to a key that is used for
         * navigation.  This is used for optimizing key input by only passing non-
         * navigation keys to the first letter navigation mechanism.
         */
        private boolean isNavigationKey(KeyEvent event) {
            InputMap inputMap = list.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
            KeyStroke key = KeyStroke.getKeyStrokeForEvent(event);

            if (inputMap != null && inputMap.get(key) != null) {
                return true;
            }
            return false;
        }

        //
        // PropertyChangeListener
        //
        public void propertyChange(PropertyChangeEvent e) {
            String propertyName = e.getPropertyName();

            /* If the JList.model property changes, remove our listener,
             * listDataListener from the old model and add it to the new one.
             */
            if (propertyName == "model") {
                @SuppressWarnings("unchecked")
                ListModel<?> oldModel = (ListModel)e.getOldValue();
                @SuppressWarnings("unchecked")
                ListModel<?> newModel = (ListModel)e.getNewValue();
                if (oldModel != null) {
                    oldModel.removeListDataListener(listDataListener);
                }
                if (newModel != null) {
                    newModel.addListDataListener(listDataListener);
                }
                updateLayoutStateNeeded |= modelChanged;
                redrawList();
            }

            /* If the JList.selectionModel property changes, remove our listener,
             * listSelectionListener from the old selectionModel and add it to the new one.
             */
            else if (propertyName == "selectionModel") {
                ListSelectionModel oldModel = (ListSelectionModel)e.getOldValue();
                ListSelectionModel newModel = (ListSelectionModel)e.getNewValue();
                if (oldModel != null) {
                    oldModel.removeListSelectionListener(listSelectionListener);
                }
                if (newModel != null) {
                    newModel.addListSelectionListener(listSelectionListener);
                }
                updateLayoutStateNeeded |= modelChanged;
                redrawList();
            }
            else if (propertyName == "cellRenderer") {
                updateLayoutStateNeeded |= cellRendererChanged;
                redrawList();
            }
            else if (propertyName == "font"
                    || SwingUtilities2.isScaleChanged(e)) {
                updateLayoutStateNeeded |= fontChanged;
                redrawList();
            }
            else if (propertyName == "prototypeCellValue") {
                updateLayoutStateNeeded |= prototypeCellValueChanged;
                redrawList();
            }
            else if (propertyName == "fixedCellHeight") {
                updateLayoutStateNeeded |= fixedCellHeightChanged;
                redrawList();
            }
            else if (propertyName == "fixedCellWidth") {
                updateLayoutStateNeeded |= fixedCellWidthChanged;
                redrawList();
            }
            else if (propertyName == "selectionForeground") {
                list.repaint();
            }
            else if (propertyName == "selectionBackground") {
                list.repaint();
            }
            else if ("layoutOrientation" == propertyName) {
                updateLayoutStateNeeded |= layoutOrientationChanged;
                layoutOrientation = list.getLayoutOrientation();
                redrawList();
            }
            else if ("visibleRowCount" == propertyName) {
                if (layoutOrientation != JList.VERTICAL) {
                    updateLayoutStateNeeded |= layoutOrientationChanged;
                    redrawList();
                }
            }
            else if ("componentOrientation" == propertyName) {
                isLeftToRight = list.getComponentOrientation().isLeftToRight();
                updateLayoutStateNeeded |= componentOrientationChanged;
                redrawList();

                InputMap inputMap = getInputMap(JComponent.WHEN_FOCUSED);
                SwingUtilities.replaceUIInputMap(list, JComponent.WHEN_FOCUSED,
                                                 inputMap);
            } else if ("List.isFileList" == propertyName) {
                updateIsFileList();
                redrawList();
            } else if ("dropLocation" == propertyName) {
                JList.DropLocation oldValue = (JList.DropLocation)e.getOldValue();
                repaintDropLocation(oldValue);
                repaintDropLocation(list.getDropLocation());
            }
        }

        private void repaintDropLocation(JList.DropLocation loc) {
            if (loc == null) {
                return;
            }

            Rectangle r;

            if (loc.isInsert()) {
                r = getDropLineRect(loc);
            } else {
                r = getCellBounds(list, loc.getIndex());
            }

            if (r != null) {
                list.repaint(r);
            }
        }

        //
        // ListDataListener
        //
        public void intervalAdded(ListDataEvent e) {
            updateLayoutStateNeeded = modelChanged;

            int minIndex = Math.min(e.getIndex0(), e.getIndex1());
            int maxIndex = Math.max(e.getIndex0(), e.getIndex1());

            /* Sync the SelectionModel with the DataModel.
             */

            ListSelectionModel sm = list.getSelectionModel();
            if (sm != null) {
                sm.insertIndexInterval(minIndex, maxIndex - minIndex+1, true);
            }

            /* Repaint the entire list, from the origin of
             * the first added cell, to the bottom of the
             * component.
             */
            redrawList();
        }


        public void intervalRemoved(ListDataEvent e)
        {
            updateLayoutStateNeeded = modelChanged;

            /* Sync the SelectionModel with the DataModel.
             */

            ListSelectionModel sm = list.getSelectionModel();
            if (sm != null) {
                sm.removeIndexInterval(e.getIndex0(), e.getIndex1());
            }

            /* Repaint the entire list, from the origin of
             * the first removed cell, to the bottom of the
             * component.
             */

            redrawList();
        }


        public void contentsChanged(ListDataEvent e) {
            updateLayoutStateNeeded = modelChanged;
            redrawList();
        }


        //
        // ListSelectionListener
        //
        public void valueChanged(ListSelectionEvent e) {
            maybeUpdateLayoutState();

            int size = list.getModel().getSize();
            int firstIndex = Math.min(size - 1, Math.max(e.getFirstIndex(), 0));
            int lastIndex = Math.min(size - 1, Math.max(e.getLastIndex(), 0));

            Rectangle bounds = getCellBounds(list, firstIndex, lastIndex);

            if (bounds != null) {
                list.repaint(bounds.x, bounds.y, bounds.width, bounds.height);
            }
        }

        //
        // MouseListener
        //
        public void mouseClicked(MouseEvent e) {
        }

        public void mouseEntered(MouseEvent e) {
        }

        public void mouseExited(MouseEvent e) {
        }

        // Whether or not the mouse press (which is being considered as part
        // of a drag sequence) also caused the selection change to be fully
        // processed.
        private boolean dragPressDidSelection;

        public void mousePressed(MouseEvent e) {
            if (SwingUtilities2.shouldIgnore(e, list)) {
                return;
            }

            boolean dragEnabled = list.getDragEnabled();
            boolean grabFocus = true;

            // different behavior if drag is enabled
            if (dragEnabled) {
                int row = SwingUtilities2.loc2IndexFileList(list, e.getPoint());
                // if we have a valid row and this is a drag initiating event
                if (row != -1 && DragRecognitionSupport.mousePressed(e)) {
                    dragPressDidSelection = false;

                    if (BasicGraphicsUtils.isMenuShortcutKeyDown(e)) {
                        // do nothing for control - will be handled on release
                        // or when drag starts
                        return;
                    } else if (!e.isShiftDown() && list.isSelectedIndex(row)) {
                        // clicking on something that's already selected
                        // and need to make it the lead now
                        list.addSelectionInterval(row, row);
                        return;
                    }

                    // could be a drag initiating event - don't grab focus
                    grabFocus = false;

                    dragPressDidSelection = true;
                }
            } else {
                // When drag is enabled mouse drags won't change the selection
                // in the list, so we only set the isAdjusting flag when it's
                // not enabled
                list.setValueIsAdjusting(true);
            }

            if (grabFocus) {
                SwingUtilities2.adjustFocus(list);
            }

            adjustSelection(e);
        }

        private void adjustSelection(MouseEvent e) {
            int row = SwingUtilities2.loc2IndexFileList(list, e.getPoint());
            if (row < 0) {
                // If shift is down in multi-select, we should do nothing.
                // For single select or non-shift-click, clear the selection
                if (isFileList &&
                    e.getID() == MouseEvent.MOUSE_PRESSED &&
                    (!e.isShiftDown() ||
                     list.getSelectionMode() == ListSelectionModel.SINGLE_SELECTION)) {
                    list.clearSelection();
                }
            }
            else {
                int anchorIndex = adjustIndex(list.getAnchorSelectionIndex(), list);
                boolean anchorSelected;
                if (anchorIndex == -1) {
                    anchorIndex = 0;
                    anchorSelected = false;
                } else {
                    anchorSelected = list.isSelectedIndex(anchorIndex);
                }

                if (BasicGraphicsUtils.isMenuShortcutKeyDown(e)) {
                    if (e.isShiftDown()) {
                        if (anchorSelected) {
                            list.addSelectionInterval(anchorIndex, row);
                        } else {
                            list.removeSelectionInterval(anchorIndex, row);
                            if (isFileList) {
                                list.addSelectionInterval(row, row);
                                list.getSelectionModel().setAnchorSelectionIndex(anchorIndex);
                            }
                        }
                    } else if (list.isSelectedIndex(row)) {
                        list.removeSelectionInterval(row, row);
                    } else {
                        list.addSelectionInterval(row, row);
                    }
                } else if (e.isShiftDown()) {
                    list.setSelectionInterval(anchorIndex, row);
                } else {
                    list.setSelectionInterval(row, row);
                }
            }
        }

        public void dragStarting(MouseEvent me) {
            if (BasicGraphicsUtils.isMenuShortcutKeyDown(me)) {
                int row = SwingUtilities2.loc2IndexFileList(list, me.getPoint());
                list.addSelectionInterval(row, row);
            }
        }

        public void mouseDragged(MouseEvent e) {
            if (SwingUtilities2.shouldIgnore(e, list)) {
                return;
            }

            if (list.getDragEnabled()) {
                DragRecognitionSupport.mouseDragged(e, this);
                return;
            }

            if (e.isShiftDown() || BasicGraphicsUtils.isMenuShortcutKeyDown(e)) {
                return;
            }

            int row = locationToIndex(list, e.getPoint());
            if (row != -1) {
                // 4835633.  Dragging onto a File should not select it.
                if (isFileList) {
                    return;
                }
                Rectangle cellBounds = getCellBounds(list, row, row);
                if (cellBounds != null) {
                    list.scrollRectToVisible(cellBounds);
                    list.setSelectionInterval(row, row);
                }
            }
        }

        public void mouseMoved(MouseEvent e) {
        }

        public void mouseReleased(MouseEvent e) {
            if (SwingUtilities2.shouldIgnore(e, list)) {
                return;
            }

            if (list.getDragEnabled()) {
                MouseEvent me = DragRecognitionSupport.mouseReleased(e);
                if (me != null) {
                    SwingUtilities2.adjustFocus(list);
                    if (!dragPressDidSelection) {
                        adjustSelection(me);
                    }
                }
            } else {
                list.setValueIsAdjusting(false);
            }
        }

        //
        // FocusListener
        //
        protected void repaintCellFocus()
        {
            int leadIndex = adjustIndex(list.getLeadSelectionIndex(), list);
            if (leadIndex != -1) {
                Rectangle r = getCellBounds(list, leadIndex, leadIndex);
                if (r != null) {
                    list.repaint(r.x, r.y, r.width, r.height);
                }
            }
        }

        /* The focusGained() focusLost() methods run when the JList
         * focus changes.
         */

        public void focusGained(FocusEvent e) {
            repaintCellFocus();
        }

        public void focusLost(FocusEvent e) {
            repaintCellFocus();
        }
    }

    private static int adjustIndex(int index, JList<?> list) {
        return index < list.getModel().getSize() ? index : -1;
    }

    private static final TransferHandler defaultTransferHandler = new ListTransferHandler();

    @SuppressWarnings("serial") // Superclass is a JDK-implementation class
    static class ListTransferHandler extends TransferHandler implements UIResource {

        
Create a Transferable to use as the source for a data transfer.
Params:
c –  The component holding the data to be transfered.  This
 argument is provided to enable sharing of TransferHandlers by
 multiple components.
Returns:
 The representation of the data to be transfered./**
         * Create a Transferable to use as the source for a data transfer.
         *
         * @param c  The component holding the data to be transfered.  This
         *  argument is provided to enable sharing of TransferHandlers by
         *  multiple components.
         * @return  The representation of the data to be transfered.
         *
         */
        @SuppressWarnings("deprecation")
        protected Transferable createTransferable(JComponent c) {
            if (c instanceof JList) {
                JList<?> list = (JList) c;
                Object[] values = list.getSelectedValues();

                if (values == null || values.length == 0) {
                    return null;
                }

                StringBuilder plainStr = new StringBuilder();
                StringBuilder htmlStr = new StringBuilder();

                htmlStr.append("<html>\n<body>\n<ul>\n");

                for (int i = 0; i < values.length; i++) {
                    Object obj = values[i];
                    String val = ((obj == null) ? "" : obj.toString());
                    plainStr.append(val).append('\n');
                    htmlStr.append("  <li>").append(val).append('\n');
                }

                // remove the last newline
                plainStr.deleteCharAt(plainStr.length() - 1);
                htmlStr.append("</ul>\n</body>\n</html>");

                return new BasicTransferable(plainStr.toString(), htmlStr.toString());
            }

            return null;
        }

        public int getSourceActions(JComponent c) {
            return COPY;
        }

    }
}