/*
 * Copyright 1997-2006 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */
package javax.swing;

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.text.*;
import java.awt.geom.*;
import java.beans.*;
import java.util.Enumeration;
import java.util.Vector;
import java.io.Serializable;
import javax.swing.event.*;
import javax.swing.border.*;
import javax.swing.plaf.*;
import javax.accessibility.*;
import javax.swing.text.*;
import javax.swing.text.html.*;
import javax.swing.plaf.basic.*;
import java.util.*;

/**
 * Defines common behaviors for buttons and menu items.
 * <p>
 * Buttons can be configured, and to some degree controlled, by
 * <code><a href="Action.html">Action</a></code>s.  Using an
 * <code>Action</code> with a button has many benefits beyond directly
 * configuring a button.  Refer to <a href="Action.html#buttonActions">
 * Swing Components Supporting <code>Action</code></a> for more
 * details, and you can find more information in <a
 * href="http://java.sun.com/docs/books/tutorial/uiswing/misc/action.html">How
 * to Use Actions</a>, a section in <em>The Java Tutorial</em>.
 * <p>
 * For further information see
 * <a
 href="http://java.sun.com/docs/books/tutorial/uiswing/components/button.html">How to Use Buttons, Check Boxes, and Radio Buttons</a>,
 * a section in <em>The Java Tutorial</em>.
 * <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<sup><font size="-2">TM</font></sup>
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Jeff Dinkins
 */
public abstract class AbstractButton extends JComponent implements ItemSelectable, SwingConstants {

    // *********************************
    // ******* Button properties *******
    // *********************************

    /** Identifies a change in the button model. */
    public static final String MODEL_CHANGED_PROPERTY = "model";
    /** Identifies a change in the button's text. */
    public static final String TEXT_CHANGED_PROPERTY = "text";
    /** Identifies a change to the button's mnemonic. */
    public static final String MNEMONIC_CHANGED_PROPERTY = "mnemonic";

    // Text positioning and alignment
    /** Identifies a change in the button's margins. */
    public static final String MARGIN_CHANGED_PROPERTY = "margin";
    /** Identifies a change in the button's vertical alignment. */
    public static final String VERTICAL_ALIGNMENT_CHANGED_PROPERTY = "verticalAlignment";
    /** Identifies a change in the button's horizontal alignment. */
    public static final String HORIZONTAL_ALIGNMENT_CHANGED_PROPERTY = "horizontalAlignment";

    /** Identifies a change in the button's vertical text position. */
    public static final String VERTICAL_TEXT_POSITION_CHANGED_PROPERTY = "verticalTextPosition";
    /** Identifies a change in the button's horizontal text position. */
    public static final String HORIZONTAL_TEXT_POSITION_CHANGED_PROPERTY = "horizontalTextPosition";

    // Paint options
    /**
     * Identifies a change to having the border drawn,
     * or having it not drawn.
     */
    public static final String BORDER_PAINTED_CHANGED_PROPERTY = "borderPainted";
    /**
     * Identifies a change to having the border highlighted when focused,
     * or not.
     */
    public static final String FOCUS_PAINTED_CHANGED_PROPERTY = "focusPainted";
    /**
     * Identifies a change from rollover enabled to disabled or back
     * to enabled.
     */
    public static final String ROLLOVER_ENABLED_CHANGED_PROPERTY = "rolloverEnabled";
    /**
     * Identifies a change to having the button paint the content area.
     */
    public static final String CONTENT_AREA_FILLED_CHANGED_PROPERTY = "contentAreaFilled";

    // Icons
    /** Identifies a change to the icon that represents the button. */
    public static final String ICON_CHANGED_PROPERTY = "icon";

    /**
     * Identifies a change to the icon used when the button has been
     * pressed.
     */
    public static final String PRESSED_ICON_CHANGED_PROPERTY = "pressedIcon";
    /**
     * Identifies a change to the icon used when the button has
     * been selected.
     */
    public static final String SELECTED_ICON_CHANGED_PROPERTY = "selectedIcon";

    /**
     * Identifies a change to the icon used when the cursor is over
     * the button.
     */
    public static final String ROLLOVER_ICON_CHANGED_PROPERTY = "rolloverIcon";
    /**
     * Identifies a change to the icon used when the cursor is
     * over the button and it has been selected.
     */
    public static final String ROLLOVER_SELECTED_ICON_CHANGED_PROPERTY = "rolloverSelectedIcon";

    /**
     * Identifies a change to the icon used when the button has
     * been disabled.
     */
    public static final String DISABLED_ICON_CHANGED_PROPERTY = "disabledIcon";
    /**
     * Identifies a change to the icon used when the button has been
     * disabled and selected.
     */
    public static final String DISABLED_SELECTED_ICON_CHANGED_PROPERTY = "disabledSelectedIcon";


    /** The data model that determines the button's state. */
    protected ButtonModel model                = null;

    private String     text                    = ""; // for BeanBox
    private Insets     margin                  = null;
    private Insets     defaultMargin           = null;

    // Button icons
    // PENDING(jeff) - hold icons in an array
    private Icon       defaultIcon             = null;
    private Icon       pressedIcon             = null;
    private Icon       disabledIcon            = null;

    private Icon       selectedIcon            = null;
    private Icon       disabledSelectedIcon    = null;

    private Icon       rolloverIcon            = null;
    private Icon       rolloverSelectedIcon    = null;

    // Display properties
    private boolean    paintBorder             = true;
    private boolean    paintFocus              = true;
    private boolean    rolloverEnabled         = false;
    private boolean    contentAreaFilled         = true;

    // Icon/Label Alignment
    private int        verticalAlignment       = CENTER;
    private int        horizontalAlignment     = CENTER;

    private int        verticalTextPosition    = CENTER;
    private int        horizontalTextPosition  = TRAILING;

    private int        iconTextGap             = 4;

    private int        mnemonic;
    private int        mnemonicIndex           = -1;

    private long       multiClickThreshhold    = 0;

    private boolean    borderPaintedSet        = false;
    private boolean    rolloverEnabledSet      = false;
    private boolean    iconTextGapSet          = false;
    private boolean    contentAreaFilledSet    = false;

    // Whether or not we've set the LayoutManager.
    private boolean setLayout = false;

    // This is only used by JButton, promoted to avoid an extra
    // boolean field in JButton
    boolean defaultCapable = true;

    /**
     * Combined listeners: ActionListener, ChangeListener, ItemListener.
     */
    private Handler handler;

    /**
     * The button model's <code>changeListener</code>.
     */
    protected ChangeListener changeListener = null;
    /**
     * The button model's <code>ActionListener</code>.
     */
    protected ActionListener actionListener = null;
    /**
     * The button model's <code>ItemListener</code>.
     */
    protected ItemListener itemListener = null;

    /**
     * Only one <code>ChangeEvent</code> is needed per button
     * instance since the
     * event's only state is the source property.  The source of events
     * generated is always "this".
     */
    protected transient ChangeEvent changeEvent;

    private boolean hideActionText = false;

    /**
     * Sets the <code>hideActionText</code> property, which determines
     * whether the button displays text from the <code>Action</code>.
     * This is useful only if an <code>Action</code> has been
     * installed on the button.
     *
     * @param hideActionText <code>true</code> if the button's
     *                       <code>text</code> property should not reflect
     *                       that of the <code>Action</code>; the default is
     *                       <code>false</code>
     * @see <a href="Action.html#buttonActions">Swing Components Supporting
     *      <code>Action</code></a>
     * @since 1.6
     * @beaninfo
     *        bound: true
     *    expert: true
     *  description: Whether the text of the button should come from
     *               the <code>Action</code>.
     */
    public void setHideActionText(boolean hideActionText) {
        if (hideActionText != this.hideActionText) {
            this.hideActionText = hideActionText;
            if (getAction() != null) {
                setTextFromAction(getAction(), false);
            }
            firePropertyChange("hideActionText", !hideActionText,
                               hideActionText);
        }
    }

    /**
     * Returns the value of the <code>hideActionText</code> property, which
     * determines whether the button displays text from the
     * <code>Action</code>.  This is useful only if an <code>Action</code>
     * has been installed on the button.
     *
     * @return <code>true</code> if the button's <code>text</code>
     *         property should not reflect that of the
     *         <code>Action</code>; the default is <code>false</code>
     * @since 1.6
     */
    public boolean getHideActionText() {
        return hideActionText;
    }

    /**
     * Returns the button's text.
     * @return the buttons text
     * @see #setText
     */
    public String getText() {
        return text;
    }

    /**
     * Sets the button's text.
     * @param text the string used to set the text
     * @see #getText
     * @beaninfo
     *        bound: true
     *    preferred: true
     *    attribute: visualUpdate true
     *  description: The button's text.
     */
    public void setText(String text) {
        String oldValue = this.text;
        this.text = text;
        firePropertyChange(TEXT_CHANGED_PROPERTY, oldValue, text);
        updateDisplayedMnemonicIndex(text, getMnemonic());

        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, text);
        }
        if (text == null || oldValue == null || !text.equals(oldValue)) {
            revalidate();
            repaint();
        }
    }


    /**
     * Returns the state of the button. True if the
     * toggle button is selected, false if it's not.
     * @return true if the toggle button is selected, otherwise false
     */
    public boolean isSelected() {
        return model.isSelected();
    }

    /**
     * Sets the state of the button. Note that this method does not
     * trigger an <code>actionEvent</code>.
     * Call <code>doClick</code> to perform a programatic action change.
     *
     * @param b  true if the button is selected, otherwise false
     */
    public void setSelected(boolean b) {
        boolean oldValue = isSelected();

        // TIGER - 4840653
        // Removed code which fired an AccessibleState.SELECTED
        // PropertyChangeEvent since this resulted in two
        // identical events being fired since
        // AbstractButton.fireItemStateChanged also fires the
        // same event. This caused screen readers to speak the
        // name of the item twice.

        model.setSelected(b);
    }

    /**
     * Programmatically perform a "click". This does the same
     * thing as if the user had pressed and released the button.
     */
    public void doClick() {
        doClick(68);
    }

    /**
     * Programmatically perform a "click". This does the same
     * thing as if the user had pressed and released the button.
     * The button stays visually "pressed" for <code>pressTime</code>
     *  milliseconds.
     *
     * @param pressTime the time to "hold down" the button, in milliseconds
     */
    public void doClick(int pressTime) {
        Dimension size = getSize();
        model.setArmed(true);
        model.setPressed(true);
        paintImmediately(new Rectangle(0,0, size.width, size.height));
        try {
            Thread.currentThread().sleep(pressTime);
        } catch(InterruptedException ie) {
        }
        model.setPressed(false);
        model.setArmed(false);
    }

    /**
     * Sets space for margin between the button's border and
     * the label. Setting to <code>null</code> will cause the button to
     * use the default margin.  The button's default <code>Border</code>
     * object will use this value to create the proper margin.
     * However, if a non-default border is set on the button,
     * it is that <code>Border</code> object's responsibility to create the
     * appropriate margin space (else this property will
     * effectively be ignored).
     *
     * @param m the space between the border and the label
     *
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The space between the button's border and the label.
     */
    public void setMargin(Insets m) {
        // Cache the old margin if it comes from the UI
        if(m instanceof UIResource) {
            defaultMargin = m;
        } else if(margin instanceof UIResource) {
            defaultMargin = margin;
        }

        // If the client passes in a null insets, restore the margin
        // from the UI if possible
        if(m == null && defaultMargin != null) {
            m = defaultMargin;
        }

        Insets old = margin;
        margin = m;
        firePropertyChange(MARGIN_CHANGED_PROPERTY, old, m);
        if (old == null || !old.equals(m)) {
            revalidate();
            repaint();
        }
    }

    /**
     * Returns the margin between the button's border and
     * the label.
     *
     * @return an <code>Insets</code> object specifying the margin
     *          between the botton's border and the label
     * @see #setMargin
     */
    public Insets getMargin() {
        return (margin == null) ? null : (Insets) margin.clone();
    }

    /**
     * Returns the default icon.
     * @return the default <code>Icon</code>
     * @see #setIcon
     */
    public Icon getIcon() {
        return defaultIcon;
    }

    /**
     * Sets the button's default icon. This icon is
     * also used as the "pressed" and "disabled" icon if
     * there is no explicitly set pressed icon.
     *
     * @param defaultIcon the icon used as the default image
     * @see #getIcon
     * @see #setPressedIcon
     * @beaninfo
     *           bound: true
     *       attribute: visualUpdate true
     *     description: The button's default icon
     */
    public void setIcon(Icon defaultIcon) {
        Icon oldValue = this.defaultIcon;
        this.defaultIcon = defaultIcon;

        /* If the default icon has really changed and we had
         * generated the disabled icon for this component,
         * (i.e. setDisabledIcon() was never called) then
         * clear the disabledIcon field.
         */
        if (defaultIcon != oldValue && (disabledIcon instanceof UIResource)) {
            disabledIcon = null;
        }

        firePropertyChange(ICON_CHANGED_PROPERTY, oldValue, defaultIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, defaultIcon);
        }
        if (defaultIcon != oldValue) {
            if (defaultIcon == null || oldValue == null ||
                defaultIcon.getIconWidth() != oldValue.getIconWidth() ||
                defaultIcon.getIconHeight() != oldValue.getIconHeight()) {
                revalidate();
            }
            repaint();
        }
    }

    /**
     * Returns the pressed icon for the button.
     * @return the <code>pressedIcon</code> property
     * @see #setPressedIcon
     */
    public Icon getPressedIcon() {
        return pressedIcon;
    }

    /**
     * Sets the pressed icon for the button.
     * @param pressedIcon the icon used as the "pressed" image
     * @see #getPressedIcon
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The pressed icon for the button.
     */
    public void setPressedIcon(Icon pressedIcon) {
        Icon oldValue = this.pressedIcon;
        this.pressedIcon = pressedIcon;
        firePropertyChange(PRESSED_ICON_CHANGED_PROPERTY, oldValue, pressedIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, pressedIcon);
        }
        if (pressedIcon != oldValue) {
            if (getModel().isPressed()) {
                repaint();
            }
        }
    }

    /**
     * Returns the selected icon for the button.
     * @return the <code>selectedIcon</code> property
     * @see #setSelectedIcon
     */
    public Icon getSelectedIcon() {
        return selectedIcon;
    }

    /**
     * Sets the selected icon for the button.
     * @param selectedIcon the icon used as the "selected" image
     * @see #getSelectedIcon
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The selected icon for the button.
     */
    public void setSelectedIcon(Icon selectedIcon) {
        Icon oldValue = this.selectedIcon;
        this.selectedIcon = selectedIcon;

        /* If the default selected icon has really changed and we had
         * generated the disabled selected icon for this component,
         * (i.e. setDisabledSelectedIcon() was never called) then
         * clear the disabledSelectedIcon field.
         */
        if (selectedIcon != oldValue &&
            disabledSelectedIcon instanceof UIResource) {

            disabledSelectedIcon = null;
        }

        firePropertyChange(SELECTED_ICON_CHANGED_PROPERTY, oldValue, selectedIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, selectedIcon);
        }
        if (selectedIcon != oldValue) {
            if (isSelected()) {
                repaint();
            }
        }
    }

    /**
     * Returns the rollover icon for the button.
     * @return the <code>rolloverIcon</code> property
     * @see #setRolloverIcon
     */
    public Icon getRolloverIcon() {
        return rolloverIcon;
    }

    /**
     * Sets the rollover icon for the button.
     * @param rolloverIcon the icon used as the "rollover" image
     * @see #getRolloverIcon
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The rollover icon for the button.
     */
    public void setRolloverIcon(Icon rolloverIcon) {
        Icon oldValue = this.rolloverIcon;
        this.rolloverIcon = rolloverIcon;
        firePropertyChange(ROLLOVER_ICON_CHANGED_PROPERTY, oldValue, rolloverIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, rolloverIcon);
        }
        setRolloverEnabled(true);
        if (rolloverIcon != oldValue) {
            // No way to determine whether we are currently in
            // a rollover state, so repaint regardless
            repaint();
        }

    }

    /**
     * Returns the rollover selection icon for the button.
     * @return the <code>rolloverSelectedIcon</code> property
     * @see #setRolloverSelectedIcon
     */
    public Icon getRolloverSelectedIcon() {
        return rolloverSelectedIcon;
    }

    /**
     * Sets the rollover selected icon for the button.
     * @param rolloverSelectedIcon the icon used as the
     *          "selected rollover" image
     * @see #getRolloverSelectedIcon
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The rollover selected icon for the button.
     */
    public void setRolloverSelectedIcon(Icon rolloverSelectedIcon) {
        Icon oldValue = this.rolloverSelectedIcon;
        this.rolloverSelectedIcon = rolloverSelectedIcon;
        firePropertyChange(ROLLOVER_SELECTED_ICON_CHANGED_PROPERTY, oldValue, rolloverSelectedIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, rolloverSelectedIcon);
        }
        setRolloverEnabled(true);
        if (rolloverSelectedIcon != oldValue) {
            // No way to determine whether we are currently in
            // a rollover state, so repaint regardless
            if (isSelected()) {
                repaint();
            }
        }
    }

    /**
     * Returns the icon used by the button when it's disabled.
     * If no disabled icon has been set this will forward the call to
     * the look and feel to construct an appropriate disabled Icon.
     * <p>
     * Some look and feels might not render the disabled Icon, in which
     * case they will ignore this.
     *
     * @return the <code>disabledIcon</code> property
     * @see #getPressedIcon
     * @see #setDisabledIcon
     * @see javax.swing.LookAndFeel#getDisabledIcon
     */
    public Icon getDisabledIcon() {
        if (disabledIcon == null) {
            disabledIcon = UIManager.getLookAndFeel().getDisabledIcon(this, getIcon());
            if (disabledIcon != null) {
                firePropertyChange(DISABLED_ICON_CHANGED_PROPERTY, null, disabledIcon);
            }
        }
        return disabledIcon;
    }

    /**
     * Sets the disabled icon for the button.
     * @param disabledIcon the icon used as the disabled image
     * @see #getDisabledIcon
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The disabled icon for the button.
     */
    public void setDisabledIcon(Icon disabledIcon) {
        Icon oldValue = this.disabledIcon;
        this.disabledIcon = disabledIcon;
        firePropertyChange(DISABLED_ICON_CHANGED_PROPERTY, oldValue, disabledIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, disabledIcon);
        }
        if (disabledIcon != oldValue) {
            if (!isEnabled()) {
                repaint();
            }
        }
    }

    /**
     * Returns the icon used by the button when it's disabled and selected.
     * If no disabled selection icon has been set, this will forward
     * the call to the LookAndFeel to construct an appropriate disabled
     * Icon from the selection icon if it has been set and to
     * <code>getDisabledIcon()</code> otherwise.
     * <p>
     * Some look and feels might not render the disabled selected Icon, in
     * which case they will ignore this.
     *
     * @return the <code>disabledSelectedIcon</code> property
     * @see #getDisabledIcon
     * @see #setDisabledSelectedIcon
     * @see javax.swing.LookAndFeel#getDisabledSelectedIcon
     */
    public Icon getDisabledSelectedIcon() {
        if (disabledSelectedIcon == null) {
             if (selectedIcon != null) {
                 disabledSelectedIcon = UIManager.getLookAndFeel().
                         getDisabledSelectedIcon(this, getSelectedIcon());
             } else {
                 return getDisabledIcon();
             }
        }
        return disabledSelectedIcon;
    }

    /**
     * Sets the disabled selection icon for the button.
     * @param disabledSelectedIcon the icon used as the disabled
     *          selection image
     * @see #getDisabledSelectedIcon
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: The disabled selection icon for the button.
     */
    public void setDisabledSelectedIcon(Icon disabledSelectedIcon) {
        Icon oldValue = this.disabledSelectedIcon;
        this.disabledSelectedIcon = disabledSelectedIcon;
        firePropertyChange(DISABLED_SELECTED_ICON_CHANGED_PROPERTY, oldValue, disabledSelectedIcon);
        if (accessibleContext != null) {
            accessibleContext.firePropertyChange(
                AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
                oldValue, disabledSelectedIcon);
        }
        if (disabledSelectedIcon != oldValue) {
            if (disabledSelectedIcon == null || oldValue == null ||
                disabledSelectedIcon.getIconWidth() != oldValue.getIconWidth() ||
                disabledSelectedIcon.getIconHeight() != oldValue.getIconHeight()) {
                revalidate();
            }
            if (!isEnabled() && isSelected()) {
                repaint();
            }
        }
    }

    /**
     * Returns the vertical alignment of the text and icon.
     *
     * @return the <code>verticalAlignment</code> property, one of the
     *          following values:
     * <ul>
     * <li>{@code SwingConstants.CENTER} (the default)
     * <li>{@code SwingConstants.TOP}
     * <li>{@code SwingConstants.BOTTOM}
     * </ul>
     */
    public int getVerticalAlignment() {
        return verticalAlignment;
    }

    /**
     * Sets the vertical alignment of the icon and text.
     * @param alignment one of the following values:
     * <ul>
     * <li>{@code SwingConstants.CENTER} (the default)
     * <li>{@code SwingConstants.TOP}
     * <li>{@code SwingConstants.BOTTOM}
     * </ul>
     * @throws IllegalArgumentException if the alignment is not one of the legal
     *         values listed above
     * @beaninfo
     *        bound: true
     *         enum: TOP    SwingConstants.TOP
     *               CENTER SwingConstants.CENTER
     *               BOTTOM  SwingConstants.BOTTOM
     *    attribute: visualUpdate true
     *  description: The vertical alignment of the icon and text.
     */
    public void setVerticalAlignment(int alignment) {
        if (alignment == verticalAlignment) return;
        int oldValue = verticalAlignment;
        verticalAlignment = checkVerticalKey(alignment, "verticalAlignment");
        firePropertyChange(VERTICAL_ALIGNMENT_CHANGED_PROPERTY, oldValue, verticalAlignment);         repaint();
    }

    /**
     * Returns the horizontal alignment of the icon and text.
     * {@code AbstractButton}'s default is {@code SwingConstants.CENTER},
     * but subclasses such as {@code JCheckBox} may use a different default.
     *
     * @return the <code>horizontalAlignment</code> property,
     *             one of the following values:
     * <ul>
     *   <li>{@code SwingConstants.RIGHT}
     *   <li>{@code SwingConstants.LEFT}
     *   <li>{@code SwingConstants.CENTER}
     *   <li>{@code SwingConstants.LEADING}
     *   <li>{@code SwingConstants.TRAILING}
     * </ul>
     */
    public int getHorizontalAlignment() {
        return horizontalAlignment;
    }

    /**
     * Sets the horizontal alignment of the icon and text.
     * {@code AbstractButton}'s default is {@code SwingConstants.CENTER},
     * but subclasses such as {@code JCheckBox} may use a different default.
     *
     * @param alignment the alignment value, one of the following values:
     * <ul>
     *   <li>{@code SwingConstants.RIGHT}
     *   <li>{@code SwingConstants.LEFT}
     *   <li>{@code SwingConstants.CENTER}
     *   <li>{@code SwingConstants.LEADING}
     *   <li>{@code SwingConstants.TRAILING}
     * </ul>
     * @throws IllegalArgumentException if the alignment is not one of the
     *         valid values
     * @beaninfo
     *        bound: true
     *         enum: LEFT     SwingConstants.LEFT
     *               CENTER   SwingConstants.CENTER
     *               RIGHT    SwingConstants.RIGHT
     *               LEADING  SwingConstants.LEADING
     *               TRAILING SwingConstants.TRAILING
     *    attribute: visualUpdate true
     *  description: The horizontal alignment of the icon and text.
     */
    public void setHorizontalAlignment(int alignment) {
        if (alignment == horizontalAlignment) return;
        int oldValue = horizontalAlignment;
        horizontalAlignment = checkHorizontalKey(alignment,
                                                 "horizontalAlignment");
        firePropertyChange(HORIZONTAL_ALIGNMENT_CHANGED_PROPERTY,
                           oldValue, horizontalAlignment);
        repaint();
    }


    /**
     * Returns the vertical position of the text relative to the icon.
     * @return the <code>verticalTextPosition</code> property,
     *          one of the following values:
     * <ul>
     * <li>{@code SwingConstants.CENTER} (the default)
     * <li>{@code SwingConstants.TOP}
     * <li>{@code SwingConstants.BOTTOM}
     * </ul>
     */
    public int getVerticalTextPosition() {
        return verticalTextPosition;
    }

    /**
     * Sets the vertical position of the text relative to the icon.
     * @param textPosition  one of the following values:
     * <ul>
     * <li>{@code SwingConstants.CENTER} (the default)
     * <li>{@code SwingConstants.TOP}
     * <li>{@code SwingConstants.BOTTOM}
     * </ul>
     * @beaninfo
     *        bound: true
     *         enum: TOP    SwingConstants.TOP
     *               CENTER SwingConstants.CENTER
     *               BOTTOM SwingConstants.BOTTOM
     *    attribute: visualUpdate true
     *  description: The vertical position of the text relative to the icon.
     */
    public void setVerticalTextPosition(int textPosition) {
        if (textPosition == verticalTextPosition) return;
        int oldValue = verticalTextPosition;
        verticalTextPosition = checkVerticalKey(textPosition, "verticalTextPosition");
        firePropertyChange(VERTICAL_TEXT_POSITION_CHANGED_PROPERTY, oldValue, verticalTextPosition);
        revalidate();
        repaint();
    }

    /**
     * Returns the horizontal position of the text relative to the icon.
     * @return the <code>horizontalTextPosition</code> property,
     *          one of the following values:
     * <ul>
     * <li>{@code SwingConstants.RIGHT}
     * <li>{@code SwingConstants.LEFT}
     * <li>{@code SwingConstants.CENTER}
     * <li>{@code SwingConstants.LEADING}
     * <li>{@code SwingConstants.TRAILING} (the default)
     * </ul>
     */
    public int getHorizontalTextPosition() {
        return horizontalTextPosition;
    }

    /**
     * Sets the horizontal position of the text relative to the icon.
     * @param textPosition one of the following values:
     * <ul>
     * <li>{@code SwingConstants.RIGHT}
     * <li>{@code SwingConstants.LEFT}
     * <li>{@code SwingConstants.CENTER}
     * <li>{@code SwingConstants.LEADING}
     * <li>{@code SwingConstants.TRAILING} (the default)
     * </ul>
     * @exception IllegalArgumentException if <code>textPosition</code>
     *          is not one of the legal values listed above
     * @beaninfo
     *        bound: true
     *         enum: LEFT     SwingConstants.LEFT
     *               CENTER   SwingConstants.CENTER
     *               RIGHT    SwingConstants.RIGHT
     *               LEADING  SwingConstants.LEADING
     *               TRAILING SwingConstants.TRAILING
     *    attribute: visualUpdate true
     *  description: The horizontal position of the text relative to the icon.
     */
    public void setHorizontalTextPosition(int textPosition) {
        if (textPosition == horizontalTextPosition) return;
        int oldValue = horizontalTextPosition;
        horizontalTextPosition = checkHorizontalKey(textPosition,
                                                    "horizontalTextPosition");
        firePropertyChange(HORIZONTAL_TEXT_POSITION_CHANGED_PROPERTY,
                           oldValue,
                           horizontalTextPosition);
        revalidate();
        repaint();
    }

    /**
     * Returns the amount of space between the text and the icon
     * displayed in this button.
     *
     * @return an int equal to the number of pixels between the text
     *         and the icon.
     * @since 1.4
     * @see #setIconTextGap
     */
    public int getIconTextGap() {
        return iconTextGap;
    }

    /**
     * If both the icon and text properties are set, this property
     * defines the space between them.
     * <p>
     * The default value of this property is 4 pixels.
     * <p>
     * This is a JavaBeans bound property.
     *
     * @since 1.4
     * @see #getIconTextGap
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: If both the icon and text properties are set, this
     *               property defines the space between them.
     */
    public void setIconTextGap(int iconTextGap) {
        int oldValue = this.iconTextGap;
        this.iconTextGap = iconTextGap;
        iconTextGapSet = true;
        firePropertyChange("iconTextGap", oldValue, iconTextGap);
        if (iconTextGap != oldValue) {
            revalidate();
            repaint();
        }
    }

    /**
     * Verify that the {@code key} argument is a legal value for the
     * {@code horizontalAlignment} and {@code horizontalTextPosition}
     * properties. Valid values are:
     * <ul>
     *   <li>{@code SwingConstants.RIGHT}
     *   <li>{@code SwingConstants.LEFT}
     *   <li>{@code SwingConstants.CENTER}
     *   <li>{@code SwingConstants.LEADING}
     *   <li>{@code SwingConstants.TRAILING}
     * </ul>
     *
     * @param key the property value to check
     * @param exception the message to use in the
     *        {@code IllegalArgumentException} that is thrown for an invalid
     *        value
     * @exception IllegalArgumentException if key is not one of the legal
     *            values listed above
     * @see #setHorizontalTextPosition
     * @see #setHorizontalAlignment
     */
    protected int checkHorizontalKey(int key, String exception) {
        if ((key == LEFT) ||
            (key == CENTER) ||
            (key == RIGHT) ||
            (key == LEADING) ||
            (key == TRAILING)) {
            return key;
        } else {
            throw new IllegalArgumentException(exception);
        }
    }

    /**
     * Verify that the {@code key} argument is a legal value for the
     * vertical properties. Valid values are:
     * <ul>
     *   <li>{@code SwingConstants.CENTER}
     *   <li>{@code SwingConstants.TOP}
     *   <li>{@code SwingConstants.BOTTOM}
     * </ul>
     *
     * @param key the property value to check
     * @param exception the message to use in the
     *        {@code IllegalArgumentException} that is thrown for an invalid
     *        value
     * @exception IllegalArgumentException if key is not one of the legal
     *            values listed above
     */
    protected int checkVerticalKey(int key, String exception) {
        if ((key == TOP) || (key == CENTER) || (key == BOTTOM)) {
            return key;
        } else {
            throw new IllegalArgumentException(exception);
        }
    }

    /**
     *{@inheritDoc}
     *
     * @since 1.6
     */
    public void removeNotify() {
        super.removeNotify();
        if(isRolloverEnabled()) {
            getModel().setRollover(false);
        }
    }

    /**
     * Sets the action command for this button.
     * @param actionCommand the action command for this button
     */
    public void setActionCommand(String actionCommand) {
        getModel().setActionCommand(actionCommand);
    }

    /**
     * Returns the action command for this button.
     * @return the action command for this button
     */
    public String getActionCommand() {
        String ac = getModel().getActionCommand();
        if(ac == null) {
            ac = getText();
        }
        return ac;
    }

    private Action action;
    private PropertyChangeListener actionPropertyChangeListener;

    /**
     * Sets the <code>Action</code>.
     * The new <code>Action</code> replaces any previously set
     * <code>Action</code> but does not affect <code>ActionListeners</code>
     * independently added with <code>addActionListener</code>.
     * If the <code>Action</code> is already a registered
     * <code>ActionListener</code> for the button, it is not re-registered.
     * <p>
     * Setting the <code>Action</code> results in immediately changing
     * all the properties described in <a href="Action.html#buttonActions">
     * Swing Components Supporting <code>Action</code></a>.
     * Subsequently, the button's properties are automatically updated
     * as the <code>Action</code>'s properties change.
     * <p>
     * This method uses three other methods to set
     * and help track the <code>Action</code>'s property values.
     * It uses the <code>configurePropertiesFromAction</code> method
     * to immediately change the button's properties.
     * To track changes in the <code>Action</code>'s property values,
     * this method registers the <code>PropertyChangeListener</code>
     * returned by <code>createActionPropertyChangeListener</code>. The
     * default {@code PropertyChangeListener} invokes the
     * {@code actionPropertyChanged} method when a property in the
     * {@code Action} changes.
     *
     * @param a the <code>Action</code> for the <code>AbstractButton</code>,
     *          or <code>null</code>
     * @since 1.3
     * @see Action
     * @see #getAction
     * @see #configurePropertiesFromAction
     * @see #createActionPropertyChangeListener
     * @see #actionPropertyChanged
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: the Action instance connected with this ActionEvent source
     */
    public void setAction(Action a) {
        Action oldValue = getAction();
        if (action==null || !action.equals(a)) {
            action = a;
            if (oldValue!=null) {
                removeActionListener(oldValue);
                oldValue.removePropertyChangeListener(actionPropertyChangeListener);
                actionPropertyChangeListener = null;
            }
            configurePropertiesFromAction(action);
            if (action!=null) {
                // Don't add if it is already a listener
                if (!isListener(ActionListener.class, action)) {
                    addActionListener(action);
                }
                // Reverse linkage:
                actionPropertyChangeListener = createActionPropertyChangeListener(action);
                action.addPropertyChangeListener(actionPropertyChangeListener);
            }
            firePropertyChange("action", oldValue, action);
        }
    }

    private boolean isListener(Class c, ActionListener a) {
        boolean isListener = false;
        Object[] listeners = listenerList.getListenerList();
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==c && listeners[i+1]==a) {
                    isListener=true;
            }
        }
        return isListener;
    }

    /**
     * Returns the currently set <code>Action</code> for this
     * <code>ActionEvent</code> source, or <code>null</code>
     * if no <code>Action</code> is set.
     *
     * @return the <code>Action</code> for this <code>ActionEvent</code>
     *          source, or <code>null</code>
     * @since 1.3
     * @see Action
     * @see #setAction
     */
    public Action getAction() {
        return action;
    }

    /**
     * Sets the properties on this button to match those in the specified
     * <code>Action</code>.  Refer to <a href="Action.html#buttonActions">
     * Swing Components Supporting <code>Action</code></a> for more
     * details as to which properties this sets.
     *
     * @param a the <code>Action</code> from which to get the properties,
     *          or <code>null</code>
     * @since 1.3
     * @see Action
     * @see #setAction
     */
    protected void configurePropertiesFromAction(Action a) {
        setMnemonicFromAction(a);
        setTextFromAction(a, false);
        AbstractAction.setToolTipTextFromAction(this, a);
        setIconFromAction(a);
        setActionCommandFromAction(a);
        AbstractAction.setEnabledFromAction(this, a);
        if (AbstractAction.hasSelectedKey(a) &&
                shouldUpdateSelectedStateFromAction()) {
            setSelectedFromAction(a);
        }
        setDisplayedMnemonicIndexFromAction(a, false);
    }

    void clientPropertyChanged(Object key, Object oldValue,
                               Object newValue) {
        if (key == "hideActionText") {
            boolean current = (newValue instanceof Boolean) ?
                                (Boolean)newValue : false;
            if (getHideActionText() != current) {
                setHideActionText(current);
            }
        }
    }

    /**
     * Button subclasses that support mirroring the selected state from
     * the action should override this to return true.  AbstractButton's
     * implementation returns false.
     */
    boolean shouldUpdateSelectedStateFromAction() {
        return false;
    }

    /**
     * Updates the button's state in response to property changes in the
     * associated action. This method is invoked from the
     * {@code PropertyChangeListener} returned from
     * {@code createActionPropertyChangeListener}. Subclasses do not normally
     * need to invoke this. Subclasses that support additional {@code Action}
     * properties should override this and
     * {@code configurePropertiesFromAction}.
     * <p>
     * Refer to the table at <a href="Action.html#buttonActions">
     * Swing Components Supporting <code>Action</code></a> for a list of
     * the properties this method sets.
     *
     * @param action the <code>Action</code> associated with this button
     * @param propertyName the name of the property that changed
     * @since 1.6
     * @see Action
     * @see #configurePropertiesFromAction
     */
    protected void actionPropertyChanged(Action action, String propertyName) {
        if (propertyName == Action.NAME) {
            setTextFromAction(action, true);
        } else if (propertyName == "enabled") {
            AbstractAction.setEnabledFromAction(this, action);
        } else if (propertyName == Action.SHORT_DESCRIPTION) {
            AbstractAction.setToolTipTextFromAction(this, action);
        } else if (propertyName == Action.SMALL_ICON) {
            smallIconChanged(action);
        } else if (propertyName == Action.MNEMONIC_KEY) {
            setMnemonicFromAction(action);
        } else if (propertyName == Action.ACTION_COMMAND_KEY) {
            setActionCommandFromAction(action);
        } else if (propertyName == Action.SELECTED_KEY &&
                   AbstractAction.hasSelectedKey(action) &&
                   shouldUpdateSelectedStateFromAction()) {
            setSelectedFromAction(action);
        } else if (propertyName == Action.DISPLAYED_MNEMONIC_INDEX_KEY) {
            setDisplayedMnemonicIndexFromAction(action, true);
        } else if (propertyName == Action.LARGE_ICON_KEY) {
            largeIconChanged(action);
        }
    }

    private void setDisplayedMnemonicIndexFromAction(
            Action a, boolean fromPropertyChange) {
        Integer iValue = (a == null) ? null :
                (Integer)a.getValue(Action.DISPLAYED_MNEMONIC_INDEX_KEY);
        if (fromPropertyChange || iValue != null) {
            int value;
            if (iValue == null) {
                value = -1;
            } else {
                value = iValue;
                String text = getText();
                if (text == null || value >= text.length()) {
                    value = -1;
                }
            }
            setDisplayedMnemonicIndex(value);
        }
    }

    private void setMnemonicFromAction(Action a) {
        Integer n = (a == null) ? null :
                                  (Integer)a.getValue(Action.MNEMONIC_KEY);
        setMnemonic((n == null) ? '\0' : n);
    }

    private void setTextFromAction(Action a, boolean propertyChange) {
        boolean hideText = getHideActionText();
        if (!propertyChange) {
            setText((a != null && !hideText) ?
                        (String)a.getValue(Action.NAME) : null);
        }
        else if (!hideText) {
            setText((String)a.getValue(Action.NAME));
        }
    }

    void setIconFromAction(Action a) {
        Icon icon = null;
        if (a != null) {
            icon = (Icon)a.getValue(Action.LARGE_ICON_KEY);
            if (icon == null) {
                icon = (Icon)a.getValue(Action.SMALL_ICON);
            }
        }
        setIcon(icon);
    }

    void smallIconChanged(Action a) {
        if (a.getValue(Action.LARGE_ICON_KEY) == null) {
            setIconFromAction(a);
        }
    }

    void largeIconChanged(Action a) {
        setIconFromAction(a);
    }

    private void setActionCommandFromAction(Action a) {
        setActionCommand((a != null) ?
                             (String)a.getValue(Action.ACTION_COMMAND_KEY) :
                             null);
    }

    /**
     * Sets the seleted state of the button from the action.  This is defined
     * here, but not wired up.  Subclasses like JToggleButton and
     * JCheckBoxMenuItem make use of it.
     *
     * @param a the Action
     */
    private void setSelectedFromAction(Action a) {
        boolean selected = false;
        if (a != null) {
            selected = AbstractAction.isSelected(a);
        }
        if (selected != isSelected()) {
            // This won't notify ActionListeners, but that should be
            // ok as the change is coming from the Action.
            setSelected(selected);
            // Make sure the change actually took effect
            if (!selected && isSelected()) {
                if (getModel() instanceof DefaultButtonModel) {
                    ButtonGroup group = (ButtonGroup)
                            ((DefaultButtonModel)getModel()).getGroup();
                    if (group != null) {
                        group.clearSelection();
                    }
                }
            }
        }
    }

    /**
     * Creates and returns a <code>PropertyChangeListener</code> that is
     * responsible for listening for changes from the specified
     * <code>Action</code> and updating the appropriate properties.
     * <p>
     * <b>Warning:</b> If you subclass this do not create an anonymous
     * inner class.  If you do the lifetime of the button will be tied to
     * that of the <code>Action</code>.
     *
     * @param a the button's action
     * @since 1.3
     * @see <a href="#actions">Actions</a>
     * @see Action
     * @see #setAction
     */
    protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
        return createActionPropertyChangeListener0(a);
    }


    PropertyChangeListener createActionPropertyChangeListener0(Action a) {
        return new ButtonActionPropertyChangeListener(this, a);
    }

    private static class ButtonActionPropertyChangeListener
                 extends ActionPropertyChangeListener<AbstractButton> {
        ButtonActionPropertyChangeListener(AbstractButton b, Action a) {
            super(b, a);
        }
        protected void actionPropertyChanged(AbstractButton button,
                                             Action action,
                                             PropertyChangeEvent e) {
            if (AbstractAction.shouldReconfigure(e)) {
                button.configurePropertiesFromAction(action);
            } else {
                button.actionPropertyChanged(action, e.getPropertyName());
            }
        }
    }

    /**
     * Gets the <code>borderPainted</code> property.
     *
     * @return the value of the <code>borderPainted</code> property
     * @see #setBorderPainted
     */
    public boolean isBorderPainted() {
        return paintBorder;
    }

    /**
     * Sets the <code>borderPainted</code> property.
     * If <code>true</code> and the button has a border,
     * the border is painted. The default value for the
     * <code>borderPainted</code> property is <code>true</code>.
     *
     * @param b if true and border property is not <code>null</code>,
     *          the border is painted
     * @see #isBorderPainted
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: Whether the border should be painted.
     */
    public void setBorderPainted(boolean b) {
        boolean oldValue = paintBorder;
        paintBorder = b;
        borderPaintedSet = true;
        firePropertyChange(BORDER_PAINTED_CHANGED_PROPERTY, oldValue, paintBorder);
        if (b != oldValue) {
            revalidate();
            repaint();
        }
    }

    /**
     * Paint the button's border if <code>BorderPainted</code>
     * property is true and the button has a border.
     * @param g the <code>Graphics</code> context in which to paint
     *
     * @see #paint
     * @see #setBorder
     */
    protected void paintBorder(Graphics g) {
        if (isBorderPainted()) {
            super.paintBorder(g);
        }
    }

    /**
     * Gets the <code>paintFocus</code> property.
     *
     * @return the <code>paintFocus</code> property
     * @see #setFocusPainted
     */
    public boolean isFocusPainted() {
        return paintFocus;
    }

    /**
     * Sets the <code>paintFocus</code> property, which must
     * be <code>true</code> for the focus state to be painted.
     * The default value for the <code>paintFocus</code> property
     * is <code>true</code>.
     * Some look and feels might not paint focus state;
     * they will ignore this property.
     *
     * @param b if <code>true</code>, the focus state should be painted
     * @see #isFocusPainted
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: Whether focus should be painted
     */
    public void setFocusPainted(boolean b) {
        boolean oldValue = paintFocus;
        paintFocus = b;
        firePropertyChange(FOCUS_PAINTED_CHANGED_PROPERTY, oldValue, paintFocus);
        if (b != oldValue && isFocusOwner()) {
            revalidate();
            repaint();
        }
    }

    /**
     * Gets the <code>contentAreaFilled</code> property.
     *
     * @return the <code>contentAreaFilled</code> property
     * @see #setContentAreaFilled
     */
    public boolean isContentAreaFilled() {
        return contentAreaFilled;
    }

    /**
     * Sets the <code>contentAreaFilled</code> property.
     * If <code>true</code> the button will paint the content
     * area.  If you wish to have a transparent button, such as
     * an icon only button, for example, then you should set
     * this to <code>false</code>. Do not call <code>setOpaque(false)</code>.
     * The default value for the the <code>contentAreaFilled</code>
     * property is <code>true</code>.
     * <p>
     * This function may cause the component's opaque property to change.
     * <p>
     * The exact behavior of calling this function varies on a
     * component-by-component and L&F-by-L&F basis.
     *
     * @param b if true, the content should be filled; if false
     *          the content area is not filled
     * @see #isContentAreaFilled
     * @see #setOpaque
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: Whether the button should paint the content area
     *               or leave it transparent.
     */
    public void setContentAreaFilled(boolean b) {
        boolean oldValue = contentAreaFilled;
        contentAreaFilled = b;
        contentAreaFilledSet = true;
        firePropertyChange(CONTENT_AREA_FILLED_CHANGED_PROPERTY, oldValue, contentAreaFilled);
        if (b != oldValue) {
            repaint();
        }
    }

    /**
     * Gets the <code>rolloverEnabled</code> property.
     *
     * @return the value of the <code>rolloverEnabled</code> property
     * @see #setRolloverEnabled
     */
    public boolean isRolloverEnabled() {
        return rolloverEnabled;
    }

    /**
     * Sets the <code>rolloverEnabled</code> property, which
     * must be <code>true</code> for rollover effects to occur.
     * The default value for the <code>rolloverEnabled</code>
     * property is <code>false</code>.
     * Some look and feels might not implement rollover effects;
     * they will ignore this property.
     *
     * @param b if <code>true</code>, rollover effects should be painted
     * @see #isRolloverEnabled
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: Whether rollover effects should be enabled.
     */
    public void setRolloverEnabled(boolean b) {
        boolean oldValue = rolloverEnabled;
        rolloverEnabled = b;
        rolloverEnabledSet = true;
        firePropertyChange(ROLLOVER_ENABLED_CHANGED_PROPERTY, oldValue, rolloverEnabled);
        if (b != oldValue) {
            repaint();
        }
    }

    /**
     * Returns the keyboard mnemonic from the the current model.
     * @return the keyboard mnemonic from the model
     */
    public int getMnemonic() {
        return mnemonic;
    }

    /**
     * Sets the keyboard mnemonic on the current model.
     * The mnemonic is the key which when combined with the look and feel's
     * mouseless modifier (usually Alt) will activate this button
     * if focus is contained somewhere within this button's ancestor
     * window.
     * <p>
     * A mnemonic must correspond to a single key on the keyboard
     * and should be specified using one of the <code>VK_XXX</code>
     * keycodes defined in <code>java.awt.event.KeyEvent</code>.
     * Mnemonics are case-insensitive, therefore a key event
     * with the corresponding keycode would cause the button to be
     * activated whether or not the Shift modifier was pressed.
     * <p>
     * If the character defined by the mnemonic is found within
     * the button's label string, the first occurrence of it
     * will be underlined to indicate the mnemonic to the user.
     *
     * @param mnemonic the key code which represents the mnemonic
     * @see     java.awt.event.KeyEvent
     * @see     #setDisplayedMnemonicIndex
     *
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: the keyboard character mnemonic
     */
    public void setMnemonic(int mnemonic) {
        int oldValue = getMnemonic();
        model.setMnemonic(mnemonic);
        updateMnemonicProperties();
    }

    /**
     * This method is now obsolete, please use <code>setMnemonic(int)</code>
     * to set the mnemonic for a button.  This method is only designed
     * to handle character values which fall between 'a' and 'z' or
     * 'A' and 'Z'.
     *
     * @param mnemonic  a char specifying the mnemonic value
     * @see #setMnemonic(int)
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: the keyboard character mnemonic
     */
    public void setMnemonic(char mnemonic) {
        int vk = (int) mnemonic;
        if(vk >= 'a' && vk <='z')
            vk -= ('a' - 'A');
        setMnemonic(vk);
    }

    /**
     * Provides a hint to the look and feel as to which character in the
     * text should be decorated to represent the mnemonic. Not all look and
     * feels may support this. A value of -1 indicates either there is no
     * mnemonic, the mnemonic character is not contained in the string, or
     * the developer does not wish the mnemonic to be displayed.
     * <p>
     * The value of this is updated as the properties relating to the
     * mnemonic change (such as the mnemonic itself, the text...).
     * You should only ever have to call this if
     * you do not wish the default character to be underlined. For example, if
     * the text was 'Save As', with a mnemonic of 'a', and you wanted the 'A'
     * to be decorated, as 'Save <u>A</u>s', you would have to invoke
     * <code>setDisplayedMnemonicIndex(5)</code> after invoking
     * <code>setMnemonic(KeyEvent.VK_A)</code>.
     *
     * @since 1.4
     * @param index Index into the String to underline
     * @exception IllegalArgumentException will be thrown if <code>index</code>
     *            is &gt;= length of the text, or &lt; -1
     * @see #getDisplayedMnemonicIndex
     *
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: the index into the String to draw the keyboard character
     *               mnemonic at
     */
    public void setDisplayedMnemonicIndex(int index)
                                          throws IllegalArgumentException {
        int oldValue = mnemonicIndex;
        if (index == -1) {
            mnemonicIndex = -1;
        } else {
            String text = getText();
            int textLength = (text == null) ? 0 : text.length();
            if (index < -1 || index >= textLength) {  // index out of range
                throw new IllegalArgumentException("index == " + index);
            }
        }
        mnemonicIndex = index;
        firePropertyChange("displayedMnemonicIndex", oldValue, index);
        if (index != oldValue) {
            revalidate();
            repaint();
        }
    }

    /**
     * Returns the character, as an index, that the look and feel should
     * provide decoration for as representing the mnemonic character.
     *
     * @since 1.4
     * @return index representing mnemonic character
     * @see #setDisplayedMnemonicIndex
     */
    public int getDisplayedMnemonicIndex() {
        return mnemonicIndex;
    }

    /**
     * Update the displayedMnemonicIndex property. This method
     * is called when either text or mnemonic changes. The new
     * value of the displayedMnemonicIndex property is the index
     * of the first occurrence of mnemonic in text.
     */
    private void updateDisplayedMnemonicIndex(String text, int mnemonic) {
        setDisplayedMnemonicIndex(
            SwingUtilities.findDisplayedMnemonicIndex(text, mnemonic));
    }

    /**
     * Brings the mnemonic property in accordance with model's mnemonic.
     * This is called when model's mnemonic changes. Also updates the
     * displayedMnemonicIndex property.
     */
    private void updateMnemonicProperties() {
        int newMnemonic = model.getMnemonic();
        if (mnemonic != newMnemonic) {
            int oldValue = mnemonic;
            mnemonic = newMnemonic;
            firePropertyChange(MNEMONIC_CHANGED_PROPERTY,
                               oldValue, mnemonic);
            updateDisplayedMnemonicIndex(getText(), mnemonic);
            revalidate();
            repaint();
        }
    }

    /**
     * Sets the amount of time (in milliseconds) required between
     * mouse press events for the button to generate the corresponding
     * action events.  After the initial mouse press occurs (and action
     * event generated) any subsequent mouse press events which occur
     * on intervals less than the threshhold will be ignored and no
     * corresponding action event generated.  By default the threshhold is 0,
     * which means that for each mouse press, an action event will be
     * fired, no matter how quickly the mouse clicks occur.  In buttons
     * where this behavior is not desirable (for example, the "OK" button
     * in a dialog), this threshhold should be set to an appropriate
     * positive value.
     *
     * @see #getMultiClickThreshhold
     * @param threshhold the amount of time required between mouse
     *        press events to generate corresponding action events
     * @exception   IllegalArgumentException if threshhold < 0
     * @since 1.4
     */
    public void setMultiClickThreshhold(long threshhold) {
        if (threshhold < 0) {
            throw new IllegalArgumentException("threshhold must be >= 0");
        }
        this.multiClickThreshhold = threshhold;
    }

    /**
     * Gets the amount of time (in milliseconds) required between
     * mouse press events for the button to generate the corresponding
     * action events.
     *
     * @see #setMultiClickThreshhold
     * @return the amount of time required between mouse press events
     *         to generate corresponding action events
     * @since 1.4
     */
    public long getMultiClickThreshhold() {
        return multiClickThreshhold;
    }

    /**
     * Returns the model that this button represents.
     * @return the <code>model</code> property
     * @see #setModel
     */
    public ButtonModel getModel() {
        return model;
    }

    /**
     * Sets the model that this button represents.
     * @param newModel the new <code>ButtonModel</code>
     * @see #getModel
     * @beaninfo
     *        bound: true
     *  description: Model that the Button uses.
     */
    public void setModel(ButtonModel newModel) {

        ButtonModel oldModel = getModel();

        if (oldModel != null) {
            oldModel.removeChangeListener(changeListener);
            oldModel.removeActionListener(actionListener);
            oldModel.removeItemListener(itemListener);
            changeListener = null;
            actionListener = null;
            itemListener = null;
        }

        model = newModel;

        if (newModel != null) {
            changeListener = createChangeListener();
            actionListener = createActionListener();
            itemListener = createItemListener();
            newModel.addChangeListener(changeListener);
            newModel.addActionListener(actionListener);
            newModel.addItemListener(itemListener);

            updateMnemonicProperties();
            //We invoke setEnabled() from JComponent
            //because setModel() can be called from a constructor
            //when the button is not fully initialized
            super.setEnabled(newModel.isEnabled());

        } else {
            mnemonic = '\0';
        }

        updateDisplayedMnemonicIndex(getText(), mnemonic);

        firePropertyChange(MODEL_CHANGED_PROPERTY, oldModel, newModel);
        if (newModel != oldModel) {
            revalidate();
            repaint();
        }
    }


    /**
     * Returns the L&F object that renders this component.
     * @return the ButtonUI object
     * @see #setUI
     */
    public ButtonUI getUI() {
        return (ButtonUI) ui;
    }


    /**
     * Sets the L&F object that renders this component.
     * @param ui the <code>ButtonUI</code> L&F object
     * @see #getUI
     * @beaninfo
     *        bound: true
     *       hidden: true
     *    attribute: visualUpdate true
     *  description: The UI object that implements the LookAndFeel.
     */
    public void setUI(ButtonUI ui) {
        super.setUI(ui);
        // disabled icons are generated by the LF so they should be unset here
        if (disabledIcon instanceof UIResource) {
            setDisabledIcon(null);
        }
        if (disabledSelectedIcon instanceof UIResource) {
            setDisabledSelectedIcon(null);
        }
    }


    /**
     * Resets the UI property to a value from the current look
     * and feel.  Subtypes of <code>AbstractButton</code>
     * should override this to update the UI. For
     * example, <code>JButton</code> might do the following:
     * <pre>
     *      setUI((ButtonUI)UIManager.getUI(
     *          "ButtonUI", "javax.swing.plaf.basic.BasicButtonUI", this));
     * </pre>
     */
    public void updateUI() {
    }

    /**
     * Adds the specified component to this container at the specified
     * index, refer to
     * {@link java.awt.Container#addImpl(Component, Object, int)}
     * for a complete description of this method.
     *
     * @param     comp the component to be added
     * @param     constraints an object expressing layout constraints
     *                 for this component
     * @param     index the position in the container's list at which to
     *                 insert the component, where <code>-1</code>
     *                 means append to the end
     * @exception IllegalArgumentException if <code>index</code> is invalid
     * @exception IllegalArgumentException if adding the container's parent
     *                  to itself
     * @exception IllegalArgumentException if adding a window to a container
     * @since 1.5
     */
    protected void addImpl(Component comp, Object constraints, int index) {
        if (!setLayout) {
            setLayout(new OverlayLayout(this));
        }
        super.addImpl(comp, constraints, index);
    }

    /**
     * Sets the layout manager for this container, refer to
     * {@link java.awt.Container#setLayout(LayoutManager)}
     * for a complete description of this method.
     *
     * @param mgr the specified layout manager
     * @since 1.5
     */
    public void setLayout(LayoutManager mgr) {
        setLayout = true;
        super.setLayout(mgr);
    }

    /**
     * Adds a <code>ChangeListener</code> to the button.
     * @param l the listener to be added
     */
    public void addChangeListener(ChangeListener l) {
        listenerList.add(ChangeListener.class, l);
    }

    /**
     * Removes a ChangeListener from the button.
     * @param l the listener to be removed
     */
    public void removeChangeListener(ChangeListener l) {
        listenerList.remove(ChangeListener.class, l);
    }

    /**
     * Returns an array of all the <code>ChangeListener</code>s added
     * to this AbstractButton with addChangeListener().
     *
     * @return all of the <code>ChangeListener</code>s added or an empty
     *         array if no listeners have been added
     * @since 1.4
     */
    public ChangeListener[] getChangeListeners() {
        return (ChangeListener[])(listenerList.getListeners(
            ChangeListener.class));
    }

    /**
     * Notifies all listeners that have registered interest for
     * notification on this event type.  The event instance
     * is lazily created.
     * @see EventListenerList
     */
    protected void fireStateChanged() {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==ChangeListener.class) {
                // Lazily create the event:
                if (changeEvent == null)
                    changeEvent = new ChangeEvent(this);
                ((ChangeListener)listeners[i+1]).stateChanged(changeEvent);
            }
        }
    }

    /**
     * Adds an <code>ActionListener</code> to the button.
     * @param l the <code>ActionListener</code> to be added
     */
    public void addActionListener(ActionListener l) {
        listenerList.add(ActionListener.class, l);
    }

    /**
     * Removes an <code>ActionListener</code> from the button.
     * If the listener is the currently set <code>Action</code>
     * for the button, then the <code>Action</code>
     * is set to <code>null</code>.
     *
     * @param l the listener to be removed
     */
    public void removeActionListener(ActionListener l) {
        if ((l != null) && (getAction() == l)) {
            setAction(null);
        } else {
            listenerList.remove(ActionListener.class, l);
        }
    }

    /**
     * Returns an array of all the <code>ActionListener</code>s added
     * to this AbstractButton with addActionListener().
     *
     * @return all of the <code>ActionListener</code>s added or an empty
     *         array if no listeners have been added
     * @since 1.4
     */
    public ActionListener[] getActionListeners() {
        return (ActionListener[])(listenerList.getListeners(
            ActionListener.class));
    }

    /**
     * Subclasses that want to handle <code>ChangeEvents</code> differently
     * can override this to return another <code>ChangeListener</code>
     * implementation.
     *
     * @return the new <code>ChangeListener</code>
     */
    protected ChangeListener createChangeListener() {
        return getHandler();
    }

    /**
     * Extends <code>ChangeListener</code> to be serializable.
     * <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<sup><font size="-2">TM</font></sup>
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     */
    protected class ButtonChangeListener implements ChangeListener, Serializable {
        // NOTE: This class is NOT used, instead the functionality has
        // been moved to Handler.
        ButtonChangeListener() {
        }

        public void stateChanged(ChangeEvent e) {
            getHandler().stateChanged(e);
        }
    }


    /**
     * Notifies all listeners that have registered interest for
     * notification on this event type.  The event instance
     * is lazily created using the <code>event</code>
     * parameter.
     *
     * @param event  the <code>ActionEvent</code> object
     * @see EventListenerList
     */
    protected void fireActionPerformed(ActionEvent event) {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        ActionEvent e = null;
        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==ActionListener.class) {
                // Lazily create the event:
                if (e == null) {
                      String actionCommand = event.getActionCommand();
                      if(actionCommand == null) {
                         actionCommand = getActionCommand();
                      }
                      e = new ActionEvent(AbstractButton.this,
                                          ActionEvent.ACTION_PERFORMED,
                                          actionCommand,
                                          event.getWhen(),
                                          event.getModifiers());
                }
                ((ActionListener)listeners[i+1]).actionPerformed(e);
            }
        }
    }

    /**
     * Notifies all listeners that have registered interest for
     * notification on this event type.  The event instance
     * is lazily created using the <code>event</code> parameter.
     *
     * @param event  the <code>ItemEvent</code> object
     * @see EventListenerList
     */
    protected void fireItemStateChanged(ItemEvent event) {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        ItemEvent e = null;
        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==ItemListener.class) {
                // Lazily create the event:
                if (e == null) {
                    e = new ItemEvent(AbstractButton.this,
                                      ItemEvent.ITEM_STATE_CHANGED,
                                      AbstractButton.this,
                                      event.getStateChange());
                }
                ((ItemListener)listeners[i+1]).itemStateChanged(e);
            }
        }
        if (accessibleContext != null) {
            if (event.getStateChange() == ItemEvent.SELECTED) {
                accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
                    null, AccessibleState.SELECTED);
                accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_VALUE_PROPERTY,
                    new Integer(0), new Integer(1));
            } else {
                accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
                    AccessibleState.SELECTED, null);
                accessibleContext.firePropertyChange(
                    AccessibleContext.ACCESSIBLE_VALUE_PROPERTY,
                    new Integer(1), new Integer(0));
            }
        }
    }


    protected ActionListener createActionListener() {
        return getHandler();
    }


    protected ItemListener createItemListener() {
        return getHandler();
    }


    /**
     * Enables (or disables) the button.
     * @param b  true to enable the button, otherwise false
     */
    public void setEnabled(boolean b) {
        if (!b && model.isRollover()) {
            model.setRollover(false);
        }
        super.setEnabled(b);
        model.setEnabled(b);
    }

    // *** Deprecated java.awt.Button APIs below *** //

    /**
     * Returns the label text.
     *
     * @return a <code>String</code> containing the label
     * @deprecated - Replaced by <code>getText</code>
     */
    @Deprecated
    public String getLabel() {
        return getText();
    }

    /**
     * Sets the label text.
     *
     * @param label  a <code>String</code> containing the text
     * @deprecated - Replaced by <code>setText(text)</code>
     * @beaninfo
     *        bound: true
     *  description: Replace by setText(text)
     */
    @Deprecated
    public void setLabel(String label) {
        setText(label);
    }

    /**
     * Adds an <code>ItemListener</code> to the <code>checkbox</code>.
     * @param l  the <code>ItemListener</code> to be added
     */
    public void addItemListener(ItemListener l) {
        listenerList.add(ItemListener.class, l);
    }

    /**
     * Removes an <code>ItemListener</code> from the button.
     * @param l the <code>ItemListener</code> to be removed
     */
    public void removeItemListener(ItemListener l) {
        listenerList.remove(ItemListener.class, l);
    }

    /**
     * Returns an array of all the <code>ItemListener</code>s added
     * to this AbstractButton with addItemListener().
     *
     * @return all of the <code>ItemListener</code>s added or an empty
     *         array if no listeners have been added
     * @since 1.4
     */
    public ItemListener[] getItemListeners() {
        return (ItemListener[])listenerList.getListeners(ItemListener.class);
    }

   /**
     * Returns an array (length 1) containing the label or
     * <code>null</code> if the button is not selected.
     *
     * @return an array containing 1 Object: the text of the button,
     *         if the item is selected; otherwise <code>null</code>
     */
    public Object[] getSelectedObjects() {
        if (isSelected() == false) {
            return null;
        }
        Object[] selectedObjects = new Object[1];
        selectedObjects[0] = getText();
        return selectedObjects;
    }

    protected void init(String text, Icon icon) {
        if(text != null) {
            setText(text);
        }

        if(icon != null) {
            setIcon(icon);
        }

        // Set the UI
        updateUI();

        setAlignmentX(LEFT_ALIGNMENT);
        setAlignmentY(CENTER_ALIGNMENT);
    }


    /**
     * This is overridden to return false if the current <code>Icon</code>'s
     * <code>Image</code> is not equal to the
     * passed in <code>Image</code> <code>img</code>.
     *
     * @param img  the <code>Image</code> to be compared
     * @param infoflags flags used to repaint the button when the image
     *          is updated and which determine how much is to be painted
     * @param x  the x coordinate
     * @param y  the y coordinate
     * @param w  the width
     * @param h  the height
     * @see     java.awt.image.ImageObserver
     * @see     java.awt.Component#imageUpdate(java.awt.Image, int, int, int, int, int)
     */
    public boolean imageUpdate(Image img, int infoflags,
                               int x, int y, int w, int h) {
        Icon iconDisplayed = getIcon();
        if (iconDisplayed == null) {
            return false;
        }

        if (!model.isEnabled()) {
            if (model.isSelected()) {
                iconDisplayed = getDisabledSelectedIcon();
            } else {
                iconDisplayed = getDisabledIcon();
            }
        } else if (model.isPressed() && model.isArmed()) {
            iconDisplayed = getPressedIcon();
        } else if (isRolloverEnabled() && model.isRollover()) {
            if (model.isSelected()) {
                iconDisplayed = getRolloverSelectedIcon();
            } else {
                iconDisplayed = getRolloverIcon();
            }
        } else if (model.isSelected()) {
            iconDisplayed = getSelectedIcon();
        }

        if (!SwingUtilities.doesIconReferenceImage(iconDisplayed, img)) {
            // We don't know about this image, disable the notification so
            // we don't keep repainting.
            return false;
        }
        return super.imageUpdate(img, infoflags, x, y, w, h);
    }

    void setUIProperty(String propertyName, Object value) {
        if (propertyName == "borderPainted") {
            if (!borderPaintedSet) {
                setBorderPainted(((Boolean)value).booleanValue());
                borderPaintedSet = false;
            }
        } else if (propertyName == "rolloverEnabled") {
            if (!rolloverEnabledSet) {
                setRolloverEnabled(((Boolean)value).booleanValue());
                rolloverEnabledSet = false;
            }
        } else if (propertyName == "iconTextGap") {
            if (!iconTextGapSet) {
                setIconTextGap(((Number)value).intValue());
                iconTextGapSet = false;
            }
        } else if (propertyName == "contentAreaFilled") {
            if (!contentAreaFilledSet) {
                setContentAreaFilled(((Boolean)value).booleanValue());
                contentAreaFilledSet = false;
            }
        } else {
            super.setUIProperty(propertyName, value);
        }
    }

    /**
     * Returns a string representation of this <code>AbstractButton</code>.
     * This method
     * is intended to be used only for debugging purposes, and the
     * content and format of the returned string may vary between
     * implementations. The returned string may be empty but may not
     * be <code>null</code>.
     * <P>
     * Overriding <code>paramString</code> to provide information about the
     * specific new aspects of the JFC components.
     *
     * @return  a string representation of this <code>AbstractButton</code>
     */
    protected String paramString() {
        String defaultIconString = ((defaultIcon != null)
                                    && (defaultIcon != this) ?
                                    defaultIcon.toString() : "");
        String pressedIconString = ((pressedIcon != null)
                                    && (pressedIcon != this) ?
                                    pressedIcon.toString() : "");
        String disabledIconString = ((disabledIcon != null)
                                     && (disabledIcon != this) ?
                                     disabledIcon.toString() : "");
        String selectedIconString = ((selectedIcon != null)
                                     && (selectedIcon != this) ?
                                     selectedIcon.toString() : "");
        String disabledSelectedIconString = ((disabledSelectedIcon != null) &&
                                             (disabledSelectedIcon != this) ?
                                             disabledSelectedIcon.toString()
                                             : "");
        String rolloverIconString = ((rolloverIcon != null)
                                     && (rolloverIcon != this) ?
                                     rolloverIcon.toString() : "");
        String rolloverSelectedIconString = ((rolloverSelectedIcon != null) &&
                                             (rolloverSelectedIcon != this) ?
                                             rolloverSelectedIcon.toString()
                                             : "");
        String paintBorderString = (paintBorder ? "true" : "false");
        String paintFocusString = (paintFocus ? "true" : "false");
        String rolloverEnabledString = (rolloverEnabled ? "true" : "false");

        return super.paramString() +
        ",defaultIcon=" + defaultIconString +
        ",disabledIcon=" + disabledIconString +
        ",disabledSelectedIcon=" + disabledSelectedIconString +
        ",margin=" + margin +
        ",paintBorder=" + paintBorderString +
        ",paintFocus=" + paintFocusString +
        ",pressedIcon=" + pressedIconString +
        ",rolloverEnabled=" + rolloverEnabledString +
        ",rolloverIcon=" + rolloverIconString +
        ",rolloverSelectedIcon=" + rolloverSelectedIconString +
        ",selectedIcon=" + selectedIconString +
        ",text=" + text;
    }


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


    //
    // Listeners that are added to model
    //
    class Handler implements ActionListener, ChangeListener, ItemListener,
                             Serializable {
        //
        // ChangeListener
        //
        public void stateChanged(ChangeEvent e) {
            Object source = e.getSource();

            updateMnemonicProperties();
            if (isEnabled() != model.isEnabled()) {
                setEnabled(model.isEnabled());
            }
            fireStateChanged();
            repaint();
        }

        //
        // ActionListener
        //
        public void actionPerformed(ActionEvent event) {
            fireActionPerformed(event);
        }

        //
        // ItemListener
        //
        public void itemStateChanged(ItemEvent event) {
            fireItemStateChanged(event);
            if (shouldUpdateSelectedStateFromAction()) {
                Action action = getAction();
                if (action != null && AbstractAction.hasSelectedKey(action)) {
                    boolean selected = isSelected();
                    boolean isActionSelected = AbstractAction.isSelected(
                              action);
                    if (isActionSelected != selected) {
                        action.putValue(Action.SELECTED_KEY, selected);
                    }
                }
            }
        }
    }

///////////////////
// Accessibility support
///////////////////
    /**
     * This class implements accessibility support for the
     * <code>AbstractButton</code> class.  It provides an implementation of the
     * Java Accessibility API appropriate to button and menu item
     * user-interface elements.
     * <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<sup><font size="-2">TM</font></sup>
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     * @since 1.4
     */
    protected abstract class AccessibleAbstractButton
        extends AccessibleJComponent implements AccessibleAction,
        AccessibleValue, AccessibleText, AccessibleExtendedComponent {

        /**
         * Returns the accessible name of this object.
         *
         * @return the localized name of the object -- can be
         *              <code>null</code> if this
         *              object does not have a name
         */
        public String getAccessibleName() {
            String name = accessibleName;

            if (name == null) {
                name = (String)getClientProperty(AccessibleContext.ACCESSIBLE_NAME_PROPERTY);
            }
            if (name == null) {
                name = AbstractButton.this.getText();
            }
            if (name == null) {
                name = super.getAccessibleName();
            }
            return name;
        }

        /**
         * Get the AccessibleIcons associated with this object if one
         * or more exist.  Otherwise return null.
         * @since 1.3
         */
        public AccessibleIcon [] getAccessibleIcon() {
            Icon defaultIcon = getIcon();

            if (defaultIcon instanceof Accessible) {
                AccessibleContext ac =
                    ((Accessible)defaultIcon).getAccessibleContext();
                if (ac != null && ac instanceof AccessibleIcon) {
                    return new AccessibleIcon[] { (AccessibleIcon)ac };
                }
            }
            return null;
        }

        /**
         * Get the state set of this object.
         *
         * @return an instance of AccessibleState containing the current state
         * of the object
         * @see AccessibleState
         */
        public AccessibleStateSet getAccessibleStateSet() {
        AccessibleStateSet states = super.getAccessibleStateSet();
            if (getModel().isArmed()) {
                states.add(AccessibleState.ARMED);
            }
            if (isFocusOwner()) {
                states.add(AccessibleState.FOCUSED);
            }
            if (getModel().isPressed()) {
                states.add(AccessibleState.PRESSED);
            }
            if (isSelected()) {
                states.add(AccessibleState.CHECKED);
            }
            return states;
        }

        /**
         * Get the AccessibleRelationSet associated with this object if one
         * exists.  Otherwise return null.
         * @see AccessibleRelation
         * @since 1.3
         */
        public AccessibleRelationSet getAccessibleRelationSet() {

            // Check where the AccessibleContext's relation
            // set already contains a MEMBER_OF relation.
            AccessibleRelationSet relationSet
                = super.getAccessibleRelationSet();

            if (!relationSet.contains(AccessibleRelation.MEMBER_OF)) {
                // get the members of the button group if one exists
                ButtonModel model = getModel();
                if (model != null && model instanceof DefaultButtonModel) {
                    ButtonGroup group = ((DefaultButtonModel)model).getGroup();
                    if (group != null) {
                        // set the target of the MEMBER_OF relation to be
                        // the members of the button group.
                        int len = group.getButtonCount();
                        Object [] target = new Object[len];
                        Enumeration elem = group.getElements();
                        for (int i = 0; i < len; i++) {
                            if (elem.hasMoreElements()) {
                                target[i] = elem.nextElement();
                            }
                        }
                        AccessibleRelation relation =
                            new AccessibleRelation(AccessibleRelation.MEMBER_OF);
                        relation.setTarget(target);
                        relationSet.add(relation);
                    }
                }
            }
            return relationSet;
        }

        /**
         * Get the AccessibleAction associated with this object.  In the
         * implementation of the Java Accessibility API for this class,
         * return this object, which is responsible for implementing the
         * AccessibleAction interface on behalf of itself.
         *
         * @return this object
         */
        public AccessibleAction getAccessibleAction() {
            return this;
        }

        /**
         * Get the AccessibleValue associated with this object.  In the
         * implementation of the Java Accessibility API for this class,
         * return this object, which is responsible for implementing the
         * AccessibleValue interface on behalf of itself.
         *
         * @return this object
         */
        public AccessibleValue getAccessibleValue() {
            return this;
        }

        /**
         * Returns the number of Actions available in this object.  The
         * default behavior of a button is to have one action - toggle
         * the button.
         *
         * @return 1, the number of Actions in this object
         */
        public int getAccessibleActionCount() {
            return 1;
        }

        /**
         * Return a description of the specified action of the object.
         *
         * @param i zero-based index of the actions
         */
        public String getAccessibleActionDescription(int i) {
            if (i == 0) {
                return UIManager.getString("AbstractButton.clickText");
            } else {
                return null;
            }
        }

        /**
         * Perform the specified Action on the object
         *
         * @param i zero-based index of actions
         * @return true if the the action was performed; else false.
         */
        public boolean doAccessibleAction(int i) {
            if (i == 0) {
                doClick();
                return true;
            } else {
                return false;
            }
        }

        /**
         * Get the value of this object as a Number.
         *
         * @return An Integer of 0 if this isn't selected or an Integer of 1 if
         * this is selected.
         * @see AbstractButton#isSelected
         */
        public Number getCurrentAccessibleValue() {
            if (isSelected()) {
                return new Integer(1);
            } else {
                return new Integer(0);
            }
        }

        /**
         * Set the value of this object as a Number.
         *
         * @return True if the value was set.
         */
        public boolean setCurrentAccessibleValue(Number n) {
            // TIGER - 4422535
            if (n == null) {
                return false;
            }
            int i = n.intValue();
            if (i == 0) {
                setSelected(false);
            } else {
                setSelected(true);
            }
            return true;
        }

        /**
         * Get the minimum value of this object as a Number.
         *
         * @return an Integer of 0.
         */
        public Number getMinimumAccessibleValue() {
            return new Integer(0);
        }

        /**
         * Get the maximum value of this object as a Number.
         *
         * @return An Integer of 1.
         */
        public Number getMaximumAccessibleValue() {
            return new Integer(1);
        }


        /* AccessibleText ---------- */

        public AccessibleText getAccessibleText() {
            View view = (View)AbstractButton.this.getClientProperty("html");
            if (view != null) {
                return this;
            } else {
                return null;
            }
        }

        /**
         * Given a point in local coordinates, return the zero-based index
         * of the character under that Point.  If the point is invalid,
         * this method returns -1.
         *
         * Note: the AbstractButton must have a valid size (e.g. have
         * been added to a parent container whose ancestor container
         * is a valid top-level window) for this method to be able
         * to return a meaningful value.
         *
         * @param p the Point in local coordinates
         * @return the zero-based index of the character under Point p; if
         * Point is invalid returns -1.
         * @since 1.3
         */
        public int getIndexAtPoint(Point p) {
            View view = (View) AbstractButton.this.getClientProperty("html");
            if (view != null) {
                Rectangle r = getTextRectangle();
                if (r == null) {
                    return -1;
                }
                Rectangle2D.Float shape =
                    new Rectangle2D.Float(r.x, r.y, r.width, r.height);
                Position.Bias bias[] = new Position.Bias[1];
                return view.viewToModel(p.x, p.y, shape, bias);
            } else {
                return -1;
            }
        }

        /**
         * Determine the bounding box of the character at the given
         * index into the string.  The bounds are returned in local
         * coordinates.  If the index is invalid an empty rectangle is
         * returned.
         *
         * Note: the AbstractButton must have a valid size (e.g. have
         * been added to a parent container whose ancestor container
         * is a valid top-level window) for this method to be able
         * to return a meaningful value.
         *
         * @param i the index into the String
         * @return the screen coordinates of the character's the bounding box,
         * if index is invalid returns an empty rectangle.
         * @since 1.3
         */
        public Rectangle getCharacterBounds(int i) {
            View view = (View) AbstractButton.this.getClientProperty("html");
            if (view != null) {
                Rectangle r = getTextRectangle();
                if (r == null) {
                    return null;
                }
                Rectangle2D.Float shape =
                    new Rectangle2D.Float(r.x, r.y, r.width, r.height);
                try {
                    Shape charShape =
                        view.modelToView(i, shape, Position.Bias.Forward);
                    return charShape.getBounds();
                } catch (BadLocationException e) {
                    return null;
                }
            } else {
                return null;
            }
        }

        /**
         * Return the number of characters (valid indicies)
         *
         * @return the number of characters
         * @since 1.3
         */
        public int getCharCount() {
            View view = (View) AbstractButton.this.getClientProperty("html");
            if (view != null) {
                Document d = view.getDocument();
                if (d instanceof StyledDocument) {
                    StyledDocument doc = (StyledDocument)d;
                    return doc.getLength();
                }
            }
            return accessibleContext.getAccessibleName().length();
        }

        /**
         * Return the zero-based offset of the caret.
         *
         * Note: That to the right of the caret will have the same index
         * value as the offset (the caret is between two characters).
         * @return the zero-based offset of the caret.
         * @since 1.3
         */
        public int getCaretPosition() {
            // There is no caret.
            return -1;
        }

        /**
         * Returns the String at a given index.
         *
         * @param part the AccessibleText.CHARACTER, AccessibleText.WORD,
         * or AccessibleText.SENTENCE to retrieve
         * @param index an index within the text >= 0
         * @return the letter, word, or sentence,
         *   null for an invalid index or part
         * @since 1.3
         */
        public String getAtIndex(int part, int index) {
            if (index < 0 || index >= getCharCount()) {
                return null;
            }
            switch (part) {
            case AccessibleText.CHARACTER:
                try {
                    return getText(index, 1);
                } catch (BadLocationException e) {
                    return null;
                }
            case AccessibleText.WORD:
                try {
                    String s = getText(0, getCharCount());
                    BreakIterator words = BreakIterator.getWordInstance(getLocale());
                    words.setText(s);
                    int end = words.following(index);
                    return s.substring(words.previous(), end);
                } catch (BadLocationException e) {
                    return null;
                }
            case AccessibleText.SENTENCE:
                try {
                    String s = getText(0, getCharCount());
                    BreakIterator sentence =
                        BreakIterator.getSentenceInstance(getLocale());
                    sentence.setText(s);
                    int end = sentence.following(index);
                    return s.substring(sentence.previous(), end);
                } catch (BadLocationException e) {
                    return null;
                }
            default:
                return null;
            }
        }

        /**
         * Returns the String after a given index.
         *
         * @param part the AccessibleText.CHARACTER, AccessibleText.WORD,
         * or AccessibleText.SENTENCE to retrieve
         * @param index an index within the text >= 0
         * @return the letter, word, or sentence, null for an invalid
         *  index or part
         * @since 1.3
         */
        public String getAfterIndex(int part, int index) {
            if (index < 0 || index >= getCharCount()) {
                return null;
            }
            switch (part) {
            case AccessibleText.CHARACTER:
                if (index+1 >= getCharCount()) {
                   return null;
                }
                try {
                    return getText(index+1, 1);
                } catch (BadLocationException e) {
                    return null;
                }
            case AccessibleText.WORD:
                try {
                    String s = getText(0, getCharCount());
                    BreakIterator words = BreakIterator.getWordInstance(getLocale());
                    words.setText(s);
                    int start = words.following(index);
                    if (start == BreakIterator.DONE || start >= s.length()) {
                        return null;
                    }
                    int end = words.following(start);
                    if (end == BreakIterator.DONE || end >= s.length()) {
                        return null;
                    }
                    return s.substring(start, end);
                } catch (BadLocationException e) {
                    return null;
                }
            case AccessibleText.SENTENCE:
                try {
                    String s = getText(0, getCharCount());
                    BreakIterator sentence =
                        BreakIterator.getSentenceInstance(getLocale());
                    sentence.setText(s);
                    int start = sentence.following(index);
                    if (start == BreakIterator.DONE || start > s.length()) {
                        return null;
                    }
                    int end = sentence.following(start);
                    if (end == BreakIterator.DONE || end > s.length()) {
                        return null;
                    }
                    return s.substring(start, end);
                } catch (BadLocationException e) {
                    return null;
                }
            default:
                return null;
            }
        }

        /**
         * Returns the String before a given index.
         *
         * @param part the AccessibleText.CHARACTER, AccessibleText.WORD,
         *   or AccessibleText.SENTENCE to retrieve
         * @param index an index within the text >= 0
         * @return the letter, word, or sentence, null for an invalid index
         *  or part
         * @since 1.3
         */
        public String getBeforeIndex(int part, int index) {
            if (index < 0 || index > getCharCount()-1) {
                return null;
            }
            switch (part) {
            case AccessibleText.CHARACTER:
                if (index == 0) {
                    return null;
                }
                try {
                    return getText(index-1, 1);
                } catch (BadLocationException e) {
                    return null;
                }
            case AccessibleText.WORD:
                try {
                    String s = getText(0, getCharCount());
                    BreakIterator words = BreakIterator.getWordInstance(getLocale());
                    words.setText(s);
                    int end = words.following(index);
                    end = words.previous();
                    int start = words.previous();
                    if (start == BreakIterator.DONE) {
                        return null;
                    }
                    return s.substring(start, end);
                } catch (BadLocationException e) {
                    return null;
                }
            case AccessibleText.SENTENCE:
                try {
                    String s = getText(0, getCharCount());
                    BreakIterator sentence =
                        BreakIterator.getSentenceInstance(getLocale());
                    sentence.setText(s);
                    int end = sentence.following(index);
                    end = sentence.previous();
                    int start = sentence.previous();
                    if (start == BreakIterator.DONE) {
                        return null;
                    }
                    return s.substring(start, end);
                } catch (BadLocationException e) {
                    return null;
                }
            default:
                return null;
            }
        }

        /**
         * Return the AttributeSet for a given character at a given index
         *
         * @param i the zero-based index into the text
         * @return the AttributeSet of the character
         * @since 1.3
         */
        public AttributeSet getCharacterAttribute(int i) {
            View view = (View) AbstractButton.this.getClientProperty("html");
            if (view != null) {
                Document d = view.getDocument();
                if (d instanceof StyledDocument) {
                    StyledDocument doc = (StyledDocument)d;
                    Element elem = doc.getCharacterElement(i);
                    if (elem != null) {
                        return elem.getAttributes();
                    }
                }
            }
            return null;
        }

        /**
         * Returns the start offset within the selected text.
         * If there is no selection, but there is
         * a caret, the start and end offsets will be the same.
         *
         * @return the index into the text of the start of the selection
         * @since 1.3
         */
        public int getSelectionStart() {
            // Text cannot be selected.
            return -1;
        }

        /**
         * Returns the end offset within the selected text.
         * If there is no selection, but there is
         * a caret, the start and end offsets will be the same.
         *
         * @return the index into teh text of the end of the selection
         * @since 1.3
         */
        public int getSelectionEnd() {
            // Text cannot be selected.
            return -1;
        }

        /**
         * Returns the portion of the text that is selected.
         *
         * @return the String portion of the text that is selected
         * @since 1.3
         */
        public String getSelectedText() {
            // Text cannot be selected.
            return null;
        }

        /*
         * Returns the text substring starting at the specified
         * offset with the specified length.
         */
        private String getText(int offset, int length)
            throws BadLocationException {

            View view = (View) AbstractButton.this.getClientProperty("html");
            if (view != null) {
                Document d = view.getDocument();
                if (d instanceof StyledDocument) {
                    StyledDocument doc = (StyledDocument)d;
                    return doc.getText(offset, length);
                }
            }
            return null;
        }

        /*
         * Returns the bounding rectangle for the component text.
         */
        private Rectangle getTextRectangle() {

            String text = AbstractButton.this.getText();
            Icon icon = (AbstractButton.this.isEnabled()) ? AbstractButton.this.getIcon() : AbstractButton.this.getDisabledIcon();

            if ((icon == null) && (text == null)) {
                return null;
            }

            Rectangle paintIconR = new Rectangle();
            Rectangle paintTextR = new Rectangle();
            Rectangle paintViewR = new Rectangle();
            Insets paintViewInsets = new Insets(0, 0, 0, 0);

            paintViewInsets = AbstractButton.this.getInsets(paintViewInsets);
            paintViewR.x = paintViewInsets.left;
            paintViewR.y = paintViewInsets.top;
            paintViewR.width = AbstractButton.this.getWidth() - (paintViewInsets.left + paintViewInsets.right);
            paintViewR.height = AbstractButton.this.getHeight() - (paintViewInsets.top + paintViewInsets.bottom);

            String clippedText = SwingUtilities.layoutCompoundLabel(
                (JComponent)AbstractButton.this,
                getFontMetrics(getFont()),
                text,
                icon,
                AbstractButton.this.getVerticalAlignment(),
                AbstractButton.this.getHorizontalAlignment(),
                AbstractButton.this.getVerticalTextPosition(),
                AbstractButton.this.getHorizontalTextPosition(),
                paintViewR,
                paintIconR,
                paintTextR,
                0);

            return paintTextR;
        }

        // ----- AccessibleExtendedComponent

        /**
         * Returns the AccessibleExtendedComponent
         *
         * @return the AccessibleExtendedComponent
         */
        AccessibleExtendedComponent getAccessibleExtendedComponent() {
            return this;
        }

        /**
         * Returns the tool tip text
         *
         * @return the tool tip text, if supported, of the object;
         * otherwise, null
         * @since 1.4
         */
        public String getToolTipText() {
            return AbstractButton.this.getToolTipText();
        }

        /**
         * Returns the titled border text
         *
         * @return the titled border text, if supported, of the object;
         * otherwise, null
         * @since 1.4
         */
        public String getTitledBorderText() {
            return super.getTitledBorderText();
        }

        /**
         * Returns key bindings associated with this object
         *
         * @return the key bindings, if supported, of the object;
         * otherwise, null
         * @see AccessibleKeyBinding
         * @since 1.4
         */
        public AccessibleKeyBinding getAccessibleKeyBinding() {
            int mnemonic = AbstractButton.this.getMnemonic();
            if (mnemonic == 0) {
                return null;
            }
            return new ButtonKeyBinding(mnemonic);
        }

        class ButtonKeyBinding implements AccessibleKeyBinding {
            int mnemonic;

            ButtonKeyBinding(int mnemonic) {
                this.mnemonic = mnemonic;
            }

            /**
             * Returns the number of key bindings for this object
             *
             * @return the zero-based number of key bindings for this object
             */
            public int getAccessibleKeyBindingCount() {
                return 1;
            }

            /**
             * Returns a key binding for this object.  The value returned is an
             * java.lang.Object which must be cast to appropriate type depending
             * on the underlying implementation of the key.  For example, if the
             * Object returned is a javax.swing.KeyStroke, the user of this
             * method should do the following:
             * <nf><code>
             * Component c = <get the component that has the key bindings>
             * AccessibleContext ac = c.getAccessibleContext();
             * AccessibleKeyBinding akb = ac.getAccessibleKeyBinding();
             * for (int i = 0; i < akb.getAccessibleKeyBindingCount(); i++) {
             *     Object o = akb.getAccessibleKeyBinding(i);
             *     if (o instanceof javax.swing.KeyStroke) {
             *         javax.swing.KeyStroke keyStroke = (javax.swing.KeyStroke)o;
             *         <do something with the key binding>
             *     }
             * }
             * </code></nf>
             *
             * @param i zero-based index of the key bindings
             * @return a javax.lang.Object which specifies the key binding
             * @exception IllegalArgumentException if the index is
             * out of bounds
             * @see #getAccessibleKeyBindingCount
             */
            public java.lang.Object getAccessibleKeyBinding(int i) {
                if (i != 0) {
                    throw new IllegalArgumentException();
                }
                return KeyStroke.getKeyStroke(mnemonic, 0);
            }
        }
    }
}