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/* * Copyright (c) 1997, 2006, Oracle and/or its affiliates. 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.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */package javax.swing; import java.util.EventListener; import java.awt.*;import java.awt.event.*;import java.awt.image.*; import java.io.ObjectOutputStream;import java.io.ObjectInputStream;import java.io.IOException; import javax.swing.plaf.*;import javax.accessibility.*;  /** * A menu item that can be selected or deselected. If selected, the menu * item typically appears with a checkmark next to it. If unselected or * deselected, the menu item appears without a checkmark. Like a regular * menu item, a check box menu item can have either text or a graphic * icon associated with it, or both. * <p> * Either <code>isSelected</code>/<code>setSelected</code> or * <code>getState</code>/<code>setState</code> can be used * to determine/specify the menu item's selection state. The * preferred methods are <code>isSelected</code> and * <code>setSelected</code>, which work for all menus and buttons. * The <code>getState</code> and <code>setState</code> methods exist for * compatibility with other component sets. * <p> * Menu items 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 menu item has many benefits beyond directly * configuring a menu item.  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 and examples of using check box menu items, * see <a href="http://java.sun.com/docs/books/tutorial/uiswing/components/menu.html">How to Use Menus</a>, * a section in <em>The Java Tutorial.</em> * <p> * <strong>Warning:</strong> Swing is not thread safe. For more * information see <a * href="package-summary.html#threading">Swing's Threading * Policy</a>. * <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}. * * @beaninfo *   attribute: isContainer false * description: A menu item which can be selected or deselected. * * @author Georges Saab * @author David Karlton */public class JCheckBoxMenuItem extends JMenuItem implements SwingConstants,        Accessible{    /**     * @see #getUIClassID     * @see #readObject     */    private static final String uiClassID = "CheckBoxMenuItemUI";     /**     * Creates an initially unselected check box menu item with no set text or icon.     */    public JCheckBoxMenuItem() {        this(null, null, false);    }     /**     * Creates an initially unselected check box menu item with an icon.     *     * @param icon the icon of the CheckBoxMenuItem.     */    public JCheckBoxMenuItem(Icon icon) {        this(null, icon, false);    }     /**     * Creates an initially unselected check box menu item with text.     *     * @param text the text of the CheckBoxMenuItem     */    public JCheckBoxMenuItem(String text) {        this(text, null, false);    }     /**     * Creates a menu item whose properties are taken from the     * Action supplied.     *     * @since 1.3     */    public JCheckBoxMenuItem(Action a) {        this();        setAction(a);    }     /**     * Creates an initially unselected check box menu item with the specified text and icon.     *     * @param text the text of the CheckBoxMenuItem     * @param icon the icon of the CheckBoxMenuItem     */    public JCheckBoxMenuItem(String text, Icon icon) {        this(text, icon, false);    }     /**     * Creates a check box menu item with the specified text and selection state.     *     * @param text the text of the check box menu item.     * @param b the selected state of the check box menu item     */    public JCheckBoxMenuItem(String text, boolean b) {        this(text, null, b);    }     /**     * Creates a check box menu item with the specified text, icon, and selection state.     *     * @param text the text of the check box menu item     * @param icon the icon of the check box menu item     * @param b the selected state of the check box menu item     */    public JCheckBoxMenuItem(String text, Icon icon, boolean b) {        super(text, icon);        setModel(new JToggleButton.ToggleButtonModel());        setSelected(b);        setFocusable(false);    }     /**     * Returns the name of the L&F class     * that renders this component.     *     * @return "CheckBoxMenuItemUI"     * @see JComponent#getUIClassID     * @see UIDefaults#getUI     */    public String getUIClassID() {        return uiClassID;    }      /**      * Returns the selected-state of the item. This method      * exists for AWT compatibility only.  New code should      * use isSelected() instead.      *      * @return true  if the item is selected      */    public boolean getState() {        return isSelected();    }     /**     * Sets the selected-state of the item. This method     * exists for AWT compatibility only.  New code should     * use setSelected() instead.     *     * @param b  a boolean value indicating the item's     *           selected-state, where true=selected     * @beaninfo     * description: The selection state of the check box menu item     *      hidden: true     */    public synchronized void setState(boolean b) {        setSelected(b);    }      /**     * Returns an array (length 1) containing the check box menu item     * label or null if the check box is not selected.     *     * @return an array containing one Object -- the text of the menu item     *         -- if the item is selected; otherwise null     */    public Object[] getSelectedObjects() {        if (isSelected() == false)            return null;        Object[] selectedObjects = new Object[1];        selectedObjects[0] = getText();        return selectedObjects;    }     /**     * See readObject() and writeObject() in JComponent for more     * information about serialization in Swing.     */    private void writeObject(ObjectOutputStream s) throws IOException {        s.defaultWriteObject();        if (getUIClassID().equals(uiClassID)) {            byte count = JComponent.getWriteObjCounter(this);            JComponent.setWriteObjCounter(this, --count);            if (count == 0 && ui != null) {                ui.installUI(this);            }        }    }      /**     * Returns a string representation of this JCheckBoxMenuItem. 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>.     *     * @return  a string representation of this JCheckBoxMenuItem.     */    protected String paramString() {        return super.paramString();    }     /**     * Overriden to return true, JCheckBoxMenuItem supports     * the selected state.     */    boolean shouldUpdateSelectedStateFromAction() {        return true;    } /////////////////// Accessibility support////////////////     /**     * Gets the AccessibleContext associated with this JCheckBoxMenuItem.     * For JCheckBoxMenuItems, the AccessibleContext takes the form of an     * AccessibleJCheckBoxMenuItem.     * A new AccessibleJCheckBoxMenuItem instance is created if necessary.     *     * @return an AccessibleJCheckBoxMenuItem that serves as the     *         AccessibleContext of this AccessibleJCheckBoxMenuItem     */    public AccessibleContext getAccessibleContext() {        if (accessibleContext == null) {            accessibleContext = new AccessibleJCheckBoxMenuItem();        }        return accessibleContext;    }     /**     * This class implements accessibility support for the     * <code>JCheckBoxMenuItem</code> class.  It provides an implementation     * of the Java Accessibility API appropriate to checkbox 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}.     */    protected class AccessibleJCheckBoxMenuItem extends AccessibleJMenuItem {        /**         * Get the role of this object.         *         * @return an instance of AccessibleRole describing the role of the         * object         */        public AccessibleRole getAccessibleRole() {            return AccessibleRole.CHECK_BOX;        }    } // inner class AccessibleJCheckBoxMenuItem}