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	/*
	* Copyright (c) 1997, 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 javax.swing;

	import java.awt.Component;
	import java.awt.Dimension;
	import java.awt.Graphics;
	import java.awt.Insets;
	import java.awt.Point;
	import java.awt.Rectangle;
	import java.awt.event.*;
	import java.beans.Transient;
	import java.util.Vector;
	import java.util.Enumeration;

	import java.io.Serializable;
	import java.io.ObjectOutputStream;
	import java.io.ObjectInputStream;
	import java.io.IOException;

	import javax.swing.event.*;
	import javax.swing.border.Border;
	import javax.swing.plaf.*;
	import javax.accessibility.*;

	/**
	* An implementation of a menu bar. You add <code>JMenu</code> objects to the
	* menu bar to construct a menu. When the user selects a <code>JMenu</code>
	* object, its associated <code>JPopupMenu</code> is displayed, allowing the
	* user to select one of the <code>JMenuItems</code> on it.
	* <p>
	* For information and examples of using menu bars see
	* <a
	href="https://docs.oracle.com/javase/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™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	* <p>
	* <strong>Warning:</strong>
	* By default, pressing the Tab key does not transfer focus from a <code>
	* JMenuBar</code> which is added to a container together with other Swing
	* components, because the <code>focusTraversalKeysEnabled</code> property
	* of <code>JMenuBar</code> is set to <code>false</code>. To resolve this,
	* you should call the <code>JMenuBar.setFocusTraversalKeysEnabled(true)</code>
	* method.
	* @beaninfo
	* attribute: isContainer true
	* description: A container for holding and displaying menus.
	*
	* @author Georges Saab
	* @author David Karlton
	* @author Arnaud Weber
	* @see JMenu
	* @see JPopupMenu
	* @see JMenuItem
	*/
	@SuppressWarnings("serial")
	public class JMenuBar extends JComponent implements Accessible,MenuElement
	{
	/**
	* @see #getUIClassID
	* @see #readObject
	*/
	private static final String uiClassID = "MenuBarUI";

	/*
	* Model for the selected subcontrol.
	*/
	private transient SingleSelectionModel selectionModel;

	private boolean paintBorder = true;
	private Insets margin = null;

	/* diagnostic aids -- should be false for production builds. */
	private static final boolean TRACE = false; // trace creates and disposes
	private static final boolean VERBOSE = false; // show reuse hits/misses
	private static final boolean DEBUG = false; // show bad params, misc.

	/**
	* Creates a new menu bar.
	*/
	public JMenuBar() {
	super();
	setFocusTraversalKeysEnabled(false);
	setSelectionModel(new DefaultSingleSelectionModel());
	updateUI();
	}

	/**
	* Returns the menubar's current UI.
	* @see #setUI
	*/
	public MenuBarUI getUI() {
	return (MenuBarUI)ui;
	}

	/**
	* Sets the L&F object that renders this component.
	*
	* @param ui the new MenuBarUI L&F object
	* @see UIDefaults#getUI
	* @beaninfo
	* bound: true
	* hidden: true
	* attribute: visualUpdate true
	* description: The UI object that implements the Component's LookAndFeel.
	*/
	public void setUI(MenuBarUI ui) {
	super.setUI(ui);
	}

	/**
	* Resets the UI property with a value from the current look and feel.
	*
	* @see JComponent#updateUI
	*/
	public void updateUI() {
	setUI((MenuBarUI)UIManager.getUI(this));
	}


	/**
	* Returns the name of the L&F class that renders this component.
	*
	* @return the string "MenuBarUI"
	* @see JComponent#getUIClassID
	* @see UIDefaults#getUI
	*/
	public String getUIClassID() {
	return uiClassID;
	}


	/**
	* Returns the model object that handles single selections.
	*
	* @return the <code>SingleSelectionModel</code> property
	* @see SingleSelectionModel
	*/
	public SingleSelectionModel getSelectionModel() {
	return selectionModel;
	}

	/**
	* Sets the model object to handle single selections.
	*
	* @param model the <code>SingleSelectionModel</code> to use
	* @see SingleSelectionModel
	* @beaninfo
	* bound: true
	* description: The selection model, recording which child is selected.
	*/
	public void setSelectionModel(SingleSelectionModel model) {
	SingleSelectionModel oldValue = selectionModel;
	this.selectionModel = model;
	firePropertyChange("selectionModel", oldValue, selectionModel);
	}


	/**
	* Appends the specified menu to the end of the menu bar.
	*
	* @param c the <code>JMenu</code> component to add
	* @return the menu component
	*/
	public JMenu add(JMenu c) {
	super.add(c);
	return c;
	}

	/**
	* Returns the menu at the specified position in the menu bar.
	*
	* @param index an integer giving the position in the menu bar, where
	* 0 is the first position
	* @return the <code>JMenu</code> at that position, or <code>null</code> if
	* if there is no <code>JMenu</code> at that position (ie. if
	* it is a <code>JMenuItem</code>)
	*/
	public JMenu getMenu(int index) {
	Component c = getComponentAtIndex(index);
	if (c instanceof JMenu)
	return (JMenu) c;
	return null;
	}

	/**
	* Returns the number of items in the menu bar.
	*
	* @return the number of items in the menu bar
	*/
	public int getMenuCount() {
	return getComponentCount();
	}

	/**
	* Sets the help menu that appears when the user selects the
	* "help" option in the menu bar. This method is not yet implemented
	* and will throw an exception.
	*
	* @param menu the JMenu that delivers help to the user
	*/
	public void setHelpMenu(JMenu menu) {
	throw new Error("setHelpMenu() not yet implemented.");
	}

	/**
	* Gets the help menu for the menu bar. This method is not yet
	* implemented and will throw an exception.
	*
	* @return the <code>JMenu</code> that delivers help to the user
	*/
	@Transient
	public JMenu getHelpMenu() {
	throw new Error("getHelpMenu() not yet implemented.");
	}

	/**
	* Returns the component at the specified index.
	*
	* @param i an integer specifying the position, where 0 is first
	* @return the <code>Component</code> at the position,
	* or <code>null</code> for an invalid index
	* @deprecated replaced by <code>getComponent(int i)</code>
	*/
	@Deprecated
	public Component getComponentAtIndex(int i) {
	if(i < 0 \|\| i >= getComponentCount()) {
	return null;
	}
	return getComponent(i);
	}

	/**
	* Returns the index of the specified component.
	*
	* @param c the <code>Component</code> to find
	* @return an integer giving the component's position, where 0 is first;
	* or -1 if it can't be found
	*/
	public int getComponentIndex(Component c) {
	int ncomponents = this.getComponentCount();
	Component[] component = this.getComponents();
	for (int i = 0 ; i < ncomponents ; i++) {
	Component comp = component[i];
	if (comp == c)
	return i;
	}
	return -1;
	}

	/**
	* Sets the currently selected component, producing a
	* a change to the selection model.
	*
	* @param sel the <code>Component</code> to select
	*/
	public void setSelected(Component sel) {
	SingleSelectionModel model = getSelectionModel();
	int index = getComponentIndex(sel);
	model.setSelectedIndex(index);
	}

	/**
	* Returns true if the menu bar currently has a component selected.
	*
	* @return true if a selection has been made, else false
	*/
	public boolean isSelected() {
	return selectionModel.isSelected();
	}

	/**
	* Returns true if the menu bars border should be painted.
	*
	* @return true if the border should be painted, else false
	*/
	public boolean isBorderPainted() {
	return paintBorder;
	}

	/**
	* Sets whether the border should be painted.
	*
	* @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;
	firePropertyChange("borderPainted", oldValue, paintBorder);
	if (b != oldValue) {
	revalidate();
	repaint();
	}
	}

	/**
	* Paints the menubar's border if <code>BorderPainted</code>
	* property is true.
	*
	* @param g the <code>Graphics</code> context to use for painting
	* @see JComponent#paint
	* @see JComponent#setBorder
	*/
	protected void paintBorder(Graphics g) {
	if (isBorderPainted()) {
	super.paintBorder(g);
	}
	}

	/**
	* Sets the margin between the menubar's border and
	* its menus. Setting to <code>null</code> will cause the menubar to
	* use the default margins.
	*
	* @param m an Insets object containing the margin values
	* @see Insets
	* @beaninfo
	* bound: true
	* attribute: visualUpdate true
	* description: The space between the menubar's border and its contents
	*/
	public void setMargin(Insets m) {
	Insets old = margin;
	this.margin = m;
	firePropertyChange("margin", old, m);
	if (old == null \|\| !old.equals(m)) {
	revalidate();
	repaint();
	}
	}

	/**
	* Returns the margin between the menubar's border and
	* its menus. If there is no previous margin, it will create
	* a default margin with zero size.
	*
	* @return an <code>Insets</code> object containing the margin values
	* @see Insets
	*/
	public Insets getMargin() {
	if(margin == null) {
	return new Insets(0,0,0,0);
	} else {
	return margin;
	}
	}


	/**
	* Implemented to be a <code>MenuElement</code> -- does nothing.
	*
	* @see #getSubElements
	*/
	public void processMouseEvent(MouseEvent event,MenuElement path[],MenuSelectionManager manager) {
	}

	/**
	* Implemented to be a <code>MenuElement</code> -- does nothing.
	*
	* @see #getSubElements
	*/
	public void processKeyEvent(KeyEvent e,MenuElement path[],MenuSelectionManager manager) {
	}

	/**
	* Implemented to be a <code>MenuElement</code> -- does nothing.
	*
	* @see #getSubElements
	*/
	public void menuSelectionChanged(boolean isIncluded) {
	}

	/**
	* Implemented to be a <code>MenuElement</code> -- returns the
	* menus in this menu bar.
	* This is the reason for implementing the <code>MenuElement</code>
	* interface -- so that the menu bar can be treated the same as
	* other menu elements.
	* @return an array of menu items in the menu bar.
	*/
	public MenuElement[] getSubElements() {
	MenuElement result[];
	Vector<MenuElement> tmp = new Vector<MenuElement>();
	int c = getComponentCount();
	int i;
	Component m;

	for(i=0 ; i < c ; i++) {
	m = getComponent(i);
	if(m instanceof MenuElement)
	tmp.addElement((MenuElement) m);
	}

	result = new MenuElement[tmp.size()];
	for(i=0,c=tmp.size() ; i < c ; i++)
	result[i] = tmp.elementAt(i);
	return result;
	}

	/**
	* Implemented to be a <code>MenuElement</code>. Returns this object.
	*
	* @return the current <code>Component</code> (this)
	* @see #getSubElements
	*/
	public Component getComponent() {
	return this;
	}


	/**
	* Returns a string representation of this <code>JMenuBar</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 a string representation of this <code>JMenuBar</code>
	*/
	protected String paramString() {
	String paintBorderString = (paintBorder ?
	"true" : "false");
	String marginString = (margin != null ?
	margin.toString() : "");

	return super.paramString() +
	",margin=" + marginString +
	",paintBorder=" + paintBorderString;
	}

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

	/**
	* Gets the AccessibleContext associated with this JMenuBar.
	* For JMenuBars, the AccessibleContext takes the form of an
	* AccessibleJMenuBar.
	* A new AccessibleJMenuBar instance is created if necessary.
	*
	* @return an AccessibleJMenuBar that serves as the
	* AccessibleContext of this JMenuBar
	*/
	public AccessibleContext getAccessibleContext() {
	if (accessibleContext == null) {
	accessibleContext = new AccessibleJMenuBar();
	}
	return accessibleContext;
	}

	/**
	* This class implements accessibility support for the
	* <code>JMenuBar</code> class. It provides an implementation of the
	* Java Accessibility API appropriate to menu bar 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™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*/
	@SuppressWarnings("serial")
	protected class AccessibleJMenuBar extends AccessibleJComponent
	implements AccessibleSelection {

	/**
	* Get the accessible state set of this object.
	*
	* @return an instance of AccessibleState containing the current state
	* of the object
	*/
	public AccessibleStateSet getAccessibleStateSet() {
	AccessibleStateSet states = super.getAccessibleStateSet();
	return states;
	}

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

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

	/**
	* Returns 1 if a menu is currently selected in this menu bar.
	*
	* @return 1 if a menu is currently selected, else 0
	*/
	public int getAccessibleSelectionCount() {
	if (isSelected()) {
	return 1;
	} else {
	return 0;
	}
	}

	/**
	* Returns the currently selected menu if one is selected,
	* otherwise null.
	*/
	public Accessible getAccessibleSelection(int i) {
	if (isSelected()) {
	if (i != 0) { // single selection model for JMenuBar
	return null;
	}
	int j = getSelectionModel().getSelectedIndex();
	if (getComponentAtIndex(j) instanceof Accessible) {
	return (Accessible) getComponentAtIndex(j);
	}
	}
	return null;
	}

	/**
	* Returns true if the current child of this object is selected.
	*
	* @param i the zero-based index of the child in this Accessible
	* object.
	* @see AccessibleContext#getAccessibleChild
	*/
	public boolean isAccessibleChildSelected(int i) {
	return (i == getSelectionModel().getSelectedIndex());
	}

	/**
	* Selects the nth menu in the menu bar, forcing it to
	* pop up. If another menu is popped up, this will force
	* it to close. If the nth menu is already selected, this
	* method has no effect.
	*
	* @param i the zero-based index of selectable items
	* @see #getAccessibleStateSet
	*/
	public void addAccessibleSelection(int i) {
	// first close up any open menu
	int j = getSelectionModel().getSelectedIndex();
	if (i == j) {
	return;
	}
	if (j >= 0 && j < getMenuCount()) {
	JMenu menu = getMenu(j);
	if (menu != null) {
	MenuSelectionManager.defaultManager().setSelectedPath(null);
	// menu.setPopupMenuVisible(false);
	}
	}
	// now popup the new menu
	getSelectionModel().setSelectedIndex(i);
	JMenu menu = getMenu(i);
	if (menu != null) {
	MenuElement me[] = new MenuElement[3];
	me[0] = JMenuBar.this;
	me[1] = menu;
	me[2] = menu.getPopupMenu();
	MenuSelectionManager.defaultManager().setSelectedPath(me);
	// menu.setPopupMenuVisible(true);
	}
	}

	/**
	* Removes the nth selected item in the object from the object's
	* selection. If the nth item isn't currently selected, this
	* method has no effect. Otherwise, it closes the popup menu.
	*
	* @param i the zero-based index of selectable items
	*/
	public void removeAccessibleSelection(int i) {
	if (i >= 0 && i < getMenuCount()) {
	JMenu menu = getMenu(i);
	if (menu != null) {
	MenuSelectionManager.defaultManager().setSelectedPath(null);
	// menu.setPopupMenuVisible(false);
	}
	getSelectionModel().setSelectedIndex(-1);
	}
	}

	/**
	* Clears the selection in the object, so that nothing in the
	* object is selected. This will close any open menu.
	*/
	public void clearAccessibleSelection() {
	int i = getSelectionModel().getSelectedIndex();
	if (i >= 0 && i < getMenuCount()) {
	JMenu menu = getMenu(i);
	if (menu != null) {
	MenuSelectionManager.defaultManager().setSelectedPath(null);
	// menu.setPopupMenuVisible(false);
	}
	}
	getSelectionModel().setSelectedIndex(-1);
	}

	/**
	* Normally causes every selected item in the object to be selected
	* if the object supports multiple selections. This method
	* makes no sense in a menu bar, and so does nothing.
	*/
	public void selectAllAccessibleSelection() {
	}
	} // internal class AccessibleJMenuBar


	/**
	* Subclassed to check all the child menus.
	* @since 1.3
	*/
	protected boolean processKeyBinding(KeyStroke ks, KeyEvent e,
	int condition, boolean pressed) {
	// See if we have a local binding.
	boolean retValue = super.processKeyBinding(ks, e, condition, pressed);
	if (!retValue) {
	MenuElement[] subElements = getSubElements();
	for (MenuElement subElement : subElements) {
	if (processBindingForKeyStrokeRecursive(
	subElement, ks, e, condition, pressed)) {
	return true;
	}
	}
	}
	return retValue;
	}

	static boolean processBindingForKeyStrokeRecursive(MenuElement elem,
	KeyStroke ks, KeyEvent e, int condition, boolean pressed) {
	if (elem == null) {
	return false;
	}

	Component c = elem.getComponent();

	if ( !(c.isVisible() \|\| (c instanceof JPopupMenu)) \|\| !c.isEnabled() ) {
	return false;
	}

	if (c != null && c instanceof JComponent &&
	((JComponent)c).processKeyBinding(ks, e, condition, pressed)) {

	return true;
	}

	MenuElement[] subElements = elem.getSubElements();
	for (MenuElement subElement : subElements) {
	if (processBindingForKeyStrokeRecursive(subElement, ks, e, condition, pressed)) {
	return true;
	// We don't, pass along to children JMenu's
	}
	}
	return false;
	}

	/**
	* Overrides <code>JComponent.addNotify</code> to register this
	* menu bar with the current keyboard manager.
	*/
	public void addNotify() {
	super.addNotify();
	KeyboardManager.getCurrentManager().registerMenuBar(this);
	}

	/**
	* Overrides <code>JComponent.removeNotify</code> to unregister this
	* menu bar with the current keyboard manager.
	*/
	public void removeNotify() {
	super.removeNotify();
	KeyboardManager.getCurrentManager().unregisterMenuBar(this);
	}


	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);
	}
	}

	Object[] kvData = new Object[4];
	int n = 0;

	if (selectionModel instanceof Serializable) {
	kvData[n++] = "selectionModel";
	kvData[n++] = selectionModel;
	}

	s.writeObject(kvData);
	}


	/**
	* See JComponent.readObject() for information about serialization
	* in Swing.
	*/
	private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException
	{
	s.defaultReadObject();
	Object[] kvData = (Object[])(s.readObject());

	for(int i = 0; i < kvData.length; i += 2) {
	if (kvData[i] == null) {
	break;
	}
	else if (kvData[i].equals("selectionModel")) {
	selectionModel = (SingleSelectionModel)kvData[i + 1];
	}
	}

	}
	}

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