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	/*
	* Copyright (c) 1995, 2013, 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 java.awt;

	import java.awt.peer.CheckboxMenuItemPeer;
	import java.awt.event.*;
	import java.util.EventListener;
	import java.io.ObjectOutputStream;
	import java.io.ObjectInputStream;
	import java.io.IOException;
	import javax.accessibility.*;
	import sun.awt.AWTAccessor;


	/**
	* This class represents a check box that can be included in a menu.
	* Selecting the check box in the menu changes its state from
	* "on" to "off" or from "off" to "on."
	* <p>
	* The following picture depicts a menu which contains an instance
	* of <code>CheckBoxMenuItem</code>:
	* <p>
	* <img src="doc-files/MenuBar-1.gif"
	* alt="Menu labeled Examples, containing items Basic, Simple, Check, and More Examples. The Check item is a CheckBoxMenuItem instance, in the off state."
	* style="float:center; margin: 7px 10px;">
	* <p>
	* The item labeled <code>Check</code> shows a check box menu item
	* in its "off" state.
	* <p>
	* When a check box menu item is selected, AWT sends an item event to
	* the item. Since the event is an instance of <code>ItemEvent</code>,
	* the <code>processEvent</code> method examines the event and passes
	* it along to <code>processItemEvent</code>. The latter method redirects
	* the event to any <code>ItemListener</code> objects that have
	* registered an interest in item events generated by this menu item.
	*
	* @author Sami Shaio
	* @see java.awt.event.ItemEvent
	* @see java.awt.event.ItemListener
	* @since JDK1.0
	*/
	public class CheckboxMenuItem extends MenuItem implements ItemSelectable, Accessible {

	static {
	/* ensure that the necessary native libraries are loaded */
	Toolkit.loadLibraries();
	if (!GraphicsEnvironment.isHeadless()) {
	initIDs();
	}

	AWTAccessor.setCheckboxMenuItemAccessor(
	new AWTAccessor.CheckboxMenuItemAccessor() {
	public boolean getState(CheckboxMenuItem cmi) {
	return cmi.state;
	}
	});
	}

	/**
	* The state of a checkbox menu item
	* @serial
	* @see #getState()
	* @see #setState(boolean)
	*/
	boolean state = false;

	transient ItemListener itemListener;

	private static final String base = "chkmenuitem";
	private static int nameCounter = 0;

	/*
	* JDK 1.1 serialVersionUID
	*/
	private static final long serialVersionUID = 6190621106981774043L;

	/**
	* Create a check box menu item with an empty label.
	* The item's state is initially set to "off."
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true
	* @see java.awt.GraphicsEnvironment#isHeadless
	* @since JDK1.1
	*/
	public CheckboxMenuItem() throws HeadlessException {
	this("", false);
	}

	/**
	* Create a check box menu item with the specified label.
	* The item's state is initially set to "off."

	* @param label a string label for the check box menu item,
	* or <code>null</code> for an unlabeled menu item.
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true
	* @see java.awt.GraphicsEnvironment#isHeadless
	*/
	public CheckboxMenuItem(String label) throws HeadlessException {
	this(label, false);
	}

	/**
	* Create a check box menu item with the specified label and state.
	* @param label a string label for the check box menu item,
	* or <code>null</code> for an unlabeled menu item.
	* @param state the initial state of the menu item, where
	* <code>true</code> indicates "on" and
	* <code>false</code> indicates "off."
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true
	* @see java.awt.GraphicsEnvironment#isHeadless
	* @since JDK1.1
	*/
	public CheckboxMenuItem(String label, boolean state)
	throws HeadlessException {
	super(label);
	this.state = state;
	}

	/**
	* Construct a name for this MenuComponent. Called by getName() when
	* the name is null.
	*/
	String constructComponentName() {
	synchronized (CheckboxMenuItem.class) {
	return base + nameCounter++;
	}
	}

	/**
	* Creates the peer of the checkbox item. This peer allows us to
	* change the look of the checkbox item without changing its
	* functionality.
	* Most applications do not call this method directly.
	* @see java.awt.Toolkit#createCheckboxMenuItem(java.awt.CheckboxMenuItem)
	* @see java.awt.Component#getToolkit()
	*/
	public void addNotify() {
	synchronized (getTreeLock()) {
	if (peer == null)
	peer = Toolkit.getDefaultToolkit().createCheckboxMenuItem(this);
	super.addNotify();
	}
	}

	/**
	* Determines whether the state of this check box menu item
	* is "on" or "off."
	*
	* @return the state of this check box menu item, where
	* <code>true</code> indicates "on" and
	* <code>false</code> indicates "off"
	* @see #setState
	*/
	public boolean getState() {
	return state;
	}

	/**
	* Sets this check box menu item to the specified state.
	* The boolean value <code>true</code> indicates "on" while
	* <code>false</code> indicates "off."
	*
	* <p>Note that this method should be primarily used to
	* initialize the state of the check box menu item.
	* Programmatically setting the state of the check box
	* menu item will <i>not</i> trigger
	* an <code>ItemEvent</code>. The only way to trigger an
	* <code>ItemEvent</code> is by user interaction.
	*
	* @param b <code>true</code> if the check box
	* menu item is on, otherwise <code>false</code>
	* @see #getState
	*/
	public synchronized void setState(boolean b) {
	state = b;
	CheckboxMenuItemPeer peer = (CheckboxMenuItemPeer)this.peer;
	if (peer != null) {
	peer.setState(b);
	}
	}

	/**
	* Returns the an array (length 1) containing the checkbox menu item
	* label or null if the checkbox is not selected.
	* @see ItemSelectable
	*/
	public synchronized Object[] getSelectedObjects() {
	if (state) {
	Object[] items = new Object[1];
	items[0] = label;
	return items;
	}
	return null;
	}

	/**
	* Adds the specified item listener to receive item events from
	* this check box menu item. Item events are sent in response to user
	* actions, but not in response to calls to setState().
	* If l is null, no exception is thrown and no action is performed.
	* <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
	* >AWT Threading Issues</a> for details on AWT's threading model.
	*
	* @param l the item listener
	* @see #removeItemListener
	* @see #getItemListeners
	* @see #setState
	* @see java.awt.event.ItemEvent
	* @see java.awt.event.ItemListener
	* @since JDK1.1
	*/
	public synchronized void addItemListener(ItemListener l) {
	if (l == null) {
	return;
	}
	itemListener = AWTEventMulticaster.add(itemListener, l);
	newEventsOnly = true;
	}

	/**
	* Removes the specified item listener so that it no longer receives
	* item events from this check box menu item.
	* If l is null, no exception is thrown and no action is performed.
	* <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
	* >AWT Threading Issues</a> for details on AWT's threading model.
	*
	* @param l the item listener
	* @see #addItemListener
	* @see #getItemListeners
	* @see java.awt.event.ItemEvent
	* @see java.awt.event.ItemListener
	* @since JDK1.1
	*/
	public synchronized void removeItemListener(ItemListener l) {
	if (l == null) {
	return;
	}
	itemListener = AWTEventMulticaster.remove(itemListener, l);
	}

	/**
	* Returns an array of all the item listeners
	* registered on this checkbox menuitem.
	*
	* @return all of this checkbox menuitem's <code>ItemListener</code>s
	* or an empty array if no item
	* listeners are currently registered
	*
	* @see #addItemListener
	* @see #removeItemListener
	* @see java.awt.event.ItemEvent
	* @see java.awt.event.ItemListener
	* @since 1.4
	*/
	public synchronized ItemListener[] getItemListeners() {
	return getListeners(ItemListener.class);
	}

	/**
	* Returns an array of all the objects currently registered
	* as <code><em>Foo</em>Listener</code>s
	* upon this <code>CheckboxMenuItem</code>.
	* <code><em>Foo</em>Listener</code>s are registered using the
	* <code>add<em>Foo</em>Listener</code> method.
	*
	* <p>
	* You can specify the <code>listenerType</code> argument
	* with a class literal, such as
	* <code><em>Foo</em>Listener.class</code>.
	* For example, you can query a
	* <code>CheckboxMenuItem</code> <code>c</code>
	* for its item listeners with the following code:
	*
	* <pre>ItemListener[] ils = (ItemListener[])(c.getListeners(ItemListener.class));</pre>
	*
	* If no such listeners exist, this method returns an empty array.
	*
	* @param listenerType the type of listeners requested; this parameter
	* should specify an interface that descends from
	* <code>java.util.EventListener</code>
	* @return an array of all objects registered as
	* <code><em>Foo</em>Listener</code>s on this checkbox menuitem,
	* or an empty array if no such
	* listeners have been added
	* @exception ClassCastException if <code>listenerType</code>
	* doesn't specify a class or interface that implements
	* <code>java.util.EventListener</code>
	*
	* @see #getItemListeners
	* @since 1.3
	*/
	public <T extends EventListener> T[] getListeners(Class<T> listenerType) {
	EventListener l = null;
	if (listenerType == ItemListener.class) {
	l = itemListener;
	} else {
	return super.getListeners(listenerType);
	}
	return AWTEventMulticaster.getListeners(l, listenerType);
	}

	// REMIND: remove when filtering is done at lower level
	boolean eventEnabled(AWTEvent e) {
	if (e.id == ItemEvent.ITEM_STATE_CHANGED) {
	if ((eventMask & AWTEvent.ITEM_EVENT_MASK) != 0 \|\|
	itemListener != null) {
	return true;
	}
	return false;
	}
	return super.eventEnabled(e);
	}

	/**
	* Processes events on this check box menu item.
	* If the event is an instance of <code>ItemEvent</code>,
	* this method invokes the <code>processItemEvent</code> method.
	* If the event is not an item event,
	* it invokes <code>processEvent</code> on the superclass.
	* <p>
	* Check box menu items currently support only item events.
	* <p>Note that if the event parameter is <code>null</code>
	* the behavior is unspecified and may result in an
	* exception.
	*
	* @param e the event
	* @see java.awt.event.ItemEvent
	* @see #processItemEvent
	* @since JDK1.1
	*/
	protected void processEvent(AWTEvent e) {
	if (e instanceof ItemEvent) {
	processItemEvent((ItemEvent)e);
	return;
	}
	super.processEvent(e);
	}

	/**
	* Processes item events occurring on this check box menu item by
	* dispatching them to any registered <code>ItemListener</code> objects.
	* <p>
	* This method is not called unless item events are
	* enabled for this menu item. Item events are enabled
	* when one of the following occurs:
	* <ul>
	* <li>An <code>ItemListener</code> object is registered
	* via <code>addItemListener</code>.
	* <li>Item events are enabled via <code>enableEvents</code>.
	* </ul>
	* <p>Note that if the event parameter is <code>null</code>
	* the behavior is unspecified and may result in an
	* exception.
	*
	* @param e the item event
	* @see java.awt.event.ItemEvent
	* @see java.awt.event.ItemListener
	* @see #addItemListener
	* @see java.awt.MenuItem#enableEvents
	* @since JDK1.1
	*/
	protected void processItemEvent(ItemEvent e) {
	ItemListener listener = itemListener;
	if (listener != null) {
	listener.itemStateChanged(e);
	}
	}

	/*
	* Post an ItemEvent and toggle state.
	*/
	void doMenuEvent(long when, int modifiers) {
	setState(!state);
	Toolkit.getEventQueue().postEvent(
	new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED,
	getLabel(),
	state ? ItemEvent.SELECTED :
	ItemEvent.DESELECTED));
	}

	/**
	* Returns a string representing the state of this
	* <code>CheckBoxMenuItem</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>.
	*
	* @return the parameter string of this check box menu item
	*/
	public String paramString() {
	return super.paramString() + ",state=" + state;
	}

	/* Serialization support.
	*/

	/*
	* Serial Data Version
	* @serial
	*/
	private int checkboxMenuItemSerializedDataVersion = 1;

	/**
	* Writes default serializable fields to stream. Writes
	* a list of serializable <code>ItemListeners</code>
	* as optional data. The non-serializable
	* <code>ItemListeners</code> are detected and
	* no attempt is made to serialize them.
	*
	* @param s the <code>ObjectOutputStream</code> to write
	* @serialData <code>null</code> terminated sequence of
	* 0 or more pairs; the pair consists of a <code>String</code>
	* and an <code>Object</code>; the <code>String</code> indicates
	* the type of object and is one of the following:
	* <code>itemListenerK</code> indicating an
	* <code>ItemListener</code> object
	*
	* @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener)
	* @see java.awt.Component#itemListenerK
	* @see #readObject(ObjectInputStream)
	*/
	private void writeObject(ObjectOutputStream s)
	throws java.io.IOException
	{
	s.defaultWriteObject();

	AWTEventMulticaster.save(s, itemListenerK, itemListener);
	s.writeObject(null);
	}

	/*
	* Reads the <code>ObjectInputStream</code> and if it
	* isn't <code>null</code> adds a listener to receive
	* item events fired by the <code>Checkbox</code> menu item.
	* Unrecognized keys or values will be ignored.
	*
	* @param s the <code>ObjectInputStream</code> to read
	* @serial
	* @see removeActionListener()
	* @see addActionListener()
	* @see #writeObject
	*/
	private void readObject(ObjectInputStream s)
	throws ClassNotFoundException, IOException
	{
	s.defaultReadObject();

	Object keyOrNull;
	while(null != (keyOrNull = s.readObject())) {
	String key = ((String)keyOrNull).intern();

	if (itemListenerK == key)
	addItemListener((ItemListener)(s.readObject()));

	else // skip value for unrecognized key
	s.readObject();
	}
	}

	/**
	* Initialize JNI field and method IDs
	*/
	private static native void initIDs();


	/////////////////
	// Accessibility support
	////////////////

	/**
	* Gets the AccessibleContext associated with this CheckboxMenuItem.
	* For checkbox menu items, the AccessibleContext takes the
	* form of an AccessibleAWTCheckboxMenuItem.
	* A new AccessibleAWTCheckboxMenuItem is created if necessary.
	*
	* @return an AccessibleAWTCheckboxMenuItem that serves as the
	* AccessibleContext of this CheckboxMenuItem
	* @since 1.3
	*/
	public AccessibleContext getAccessibleContext() {
	if (accessibleContext == null) {
	accessibleContext = new AccessibleAWTCheckboxMenuItem();
	}
	return accessibleContext;
	}

	/**
	* Inner class of CheckboxMenuItem used to provide default support for
	* accessibility. This class is not meant to be used directly by
	* application developers, but is instead meant only to be
	* subclassed by menu component developers.
	* <p>
	* This class implements accessibility support for the
	* <code>CheckboxMenuItem</code> class. It provides an implementation
	* of the Java Accessibility API appropriate to checkbox menu item
	* user-interface elements.
	* @since 1.3
	*/
	protected class AccessibleAWTCheckboxMenuItem extends AccessibleAWTMenuItem
	implements AccessibleAction, AccessibleValue
	{
	/*
	* JDK 1.3 serialVersionUID
	*/
	private static final long serialVersionUID = -1122642964303476L;

	/**
	* 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.
	* If there is more than one, the first one is the "default"
	* action.
	*
	* @return the number of Actions in this object
	*/
	public int getAccessibleActionCount() {
	return 0; // To be fully implemented in a future release
	}

	/**
	* Return a description of the specified action of the object.
	*
	* @param i zero-based index of the actions
	*/
	public String getAccessibleActionDescription(int i) {
	return null; // To be fully implemented in a future release
	}

	/**
	* Perform the specified Action on the object
	*
	* @param i zero-based index of actions
	* @return true if the action was performed; otherwise false.
	*/
	public boolean doAccessibleAction(int i) {
	return false; // To be fully implemented in a future release
	}

	/**
	* Get the value of this object as a Number. If the value has not been
	* set, the return value will be null.
	*
	* @return value of the object
	* @see #setCurrentAccessibleValue
	*/
	public Number getCurrentAccessibleValue() {
	return null; // To be fully implemented in a future release
	}

	/**
	* Set the value of this object as a Number.
	*
	* @return true if the value was set; otherwise false
	* @see #getCurrentAccessibleValue
	*/
	public boolean setCurrentAccessibleValue(Number n) {
	return false; // To be fully implemented in a future release
	}

	/**
	* Get the minimum value of this object as a Number.
	*
	* @return Minimum value of the object; null if this object does not
	* have a minimum value
	* @see #getMaximumAccessibleValue
	*/
	public Number getMinimumAccessibleValue() {
	return null; // To be fully implemented in a future release
	}

	/**
	* Get the maximum value of this object as a Number.
	*
	* @return Maximum value of the object; null if this object does not
	* have a maximum value
	* @see #getMinimumAccessibleValue
	*/
	public Number getMaximumAccessibleValue() {
	return null; // To be fully implemented in a future release
	}

	/**
	* Get the role of this object.
	*
	* @return an instance of AccessibleRole describing the role of the
	* object
	*/
	public AccessibleRole getAccessibleRole() {
	return AccessibleRole.CHECK_BOX;
	}

	} // class AccessibleAWTMenuItem

	}

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