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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.applet.Applet;
	import java.awt.*;
	import java.awt.event.*;
	import java.beans.*;
	import java.security.AccessController;
	import javax.accessibility.*;
	import javax.swing.plaf.RootPaneUI;
	import java.util.Vector;
	import java.io.Serializable;
	import javax.swing.border.*;
	import sun.awt.AWTAccessor;
	import sun.security.action.GetBooleanAction;


	/**
	* A lightweight container used behind the scenes by
	* <code>JFrame</code>, <code>JDialog</code>, <code>JWindow</code>,
	* <code>JApplet</code>, and <code>JInternalFrame</code>.
	* For task-oriented information on functionality provided by root panes
	* see <a href="https://docs.oracle.com/javase/tutorial/uiswing/components/rootpane.html">How to Use Root Panes</a>,
	* a section in <em>The Java Tutorial</em>.
	*
	* <p>
	* The following image shows the relationships between
	* the classes that use root panes.
	* <p style="text-align:center"><img src="doc-files/JRootPane-1.gif"
	* alt="The following text describes this graphic."
	* HEIGHT=484 WIDTH=629></p>
	* The "heavyweight" components (those that delegate to a peer, or native
	* component on the host system) are shown with a darker, heavier box. The four
	* heavyweight JFC/Swing containers (<code>JFrame</code>, <code>JDialog</code>,
	* <code>JWindow</code>, and <code>JApplet</code>) are
	* shown in relation to the AWT classes they extend.
	* These four components are the
	* only heavyweight containers in the Swing library. The lightweight container
	* <code>JInternalFrame</code> is also shown.
	* All five of these JFC/Swing containers implement the
	* <code>RootPaneContainer</code> interface,
	* and they all delegate their operations to a
	* <code>JRootPane</code> (shown with a little "handle" on top).
	* <blockquote>
	* <b>Note:</b> The <code>JComponent</code> method <code>getRootPane</code>
	* can be used to obtain the <code>JRootPane</code> that contains
	* a given component.
	* </blockquote>
	* <table style="float:right" border="0" summary="layout">
	* <tr>
	* <td align="center">
	* <img src="doc-files/JRootPane-2.gif"
	* alt="The following text describes this graphic." HEIGHT=386 WIDTH=349>
	* </td>
	* </tr>
	* </table>
	* The diagram at right shows the structure of a <code>JRootPane</code>.
	* A <code>JRootpane</code> is made up of a <code>glassPane</code>,
	* an optional <code>menuBar</code>, and a <code>contentPane</code>.
	* (The <code>JLayeredPane</code> manages the <code>menuBar</code>
	* and the <code>contentPane</code>.)
	* The <code>glassPane</code> sits over the top of everything,
	* where it is in a position to intercept mouse movements.
	* Since the <code>glassPane</code> (like the <code>contentPane</code>)
	* can be an arbitrary component, it is also possible to set up the
	* <code>glassPane</code> for drawing. Lines and images on the
	* <code>glassPane</code> can then range
	* over the frames underneath without being limited by their boundaries.
	* <p>
	* Although the <code>menuBar</code> component is optional,
	* the <code>layeredPane</code>, <code>contentPane</code>,
	* and <code>glassPane</code> always exist.
	* Attempting to set them to <code>null</code> generates an exception.
	* <p>
	* To add components to the <code>JRootPane</code> (other than the
	* optional menu bar), you add the object to the <code>contentPane</code>
	* of the <code>JRootPane</code>, like this:
	* <pre>
	* rootPane.getContentPane().add(child);
	* </pre>
	* The same principle holds true for setting layout managers, removing
	* components, listing children, etc. All these methods are invoked on
	* the <code>contentPane</code> instead of on the <code>JRootPane</code>.
	* <blockquote>
	* <b>Note:</b> The default layout manager for the <code>contentPane</code> is
	* a <code>BorderLayout</code> manager. However, the <code>JRootPane</code>
	* uses a custom <code>LayoutManager</code>.
	* So, when you want to change the layout manager for the components you added
	* to a <code>JRootPane</code>, be sure to use code like this:
	* <pre>
	* rootPane.getContentPane().setLayout(new BoxLayout());
	* </pre></blockquote>
	* If a <code>JMenuBar</code> component is set on the <code>JRootPane</code>,
	* it is positioned along the upper edge of the frame.
	* The <code>contentPane</code> is adjusted in location and size to
	* fill the remaining area.
	* (The <code>JMenuBar</code> and the <code>contentPane</code> are added to the
	* <code>layeredPane</code> component at the
	* <code>JLayeredPane.FRAME_CONTENT_LAYER</code> layer.)
	* <p>
	* The <code>layeredPane</code> is the parent of all children in the
	* <code>JRootPane</code> -- both as the direct parent of the menu and
	* the grandparent of all components added to the <code>contentPane</code>.
	* It is an instance of <code>JLayeredPane</code>,
	* which provides the ability to add components at several layers.
	* This capability is very useful when working with menu popups,
	* dialog boxes, and dragging -- situations in which you need to place
	* a component on top of all other components in the pane.
	* <p>
	* The <code>glassPane</code> sits on top of all other components in the
	* <code>JRootPane</code>.
	* That provides a convenient place to draw above all other components,
	* and makes it possible to intercept mouse events,
	* which is useful both for dragging and for drawing.
	* Developers can use <code>setVisible</code> on the <code>glassPane</code>
	* to control when the <code>glassPane</code> displays over the other children.
	* By default the <code>glassPane</code> is not visible.
	* <p>
	* The custom <code>LayoutManager</code> used by <code>JRootPane</code>
	* ensures that:
	* <OL>
	* <LI>The <code>glassPane</code> fills the entire viewable
	* area of the <code>JRootPane</code> (bounds - insets).
	* <LI>The <code>layeredPane</code> fills the entire viewable area of the
	* <code>JRootPane</code>. (bounds - insets)
	* <LI>The <code>menuBar</code> is positioned at the upper edge of the
	* <code>layeredPane</code>.
	* <LI>The <code>contentPane</code> fills the entire viewable area,
	* minus the <code>menuBar</code>, if present.
	* </OL>
	* Any other views in the <code>JRootPane</code> view hierarchy are ignored.
	* <p>
	* If you replace the <code>LayoutManager</code> of the <code>JRootPane</code>,
	* you are responsible for managing all of these views.
	* So ordinarily you will want to be sure that you
	* change the layout manager for the <code>contentPane</code> rather than
	* for the <code>JRootPane</code> itself!
	* <p>
	* The painting architecture of Swing requires an opaque
	* <code>JComponent</code>
	* to exist in the containment hierarchy above all other components. This is
	* typically provided by way of the content pane. If you replace the content
	* pane, it is recommended that you make the content pane opaque
	* by way of <code>setOpaque(true)</code>. Additionally, if the content pane
	* overrides <code>paintComponent</code>, it
	* will need to completely fill in the background in an opaque color in
	* <code>paintComponent</code>.
	* <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}.
	*
	* @see JLayeredPane
	* @see JMenuBar
	* @see JWindow
	* @see JFrame
	* @see JDialog
	* @see JApplet
	* @see JInternalFrame
	* @see JComponent
	* @see BoxLayout
	*
	* @see <a href="http://java.sun.com/products/jfc/tsc/articles/mixing/">
	* Mixing Heavy and Light Components</a>
	*
	* @author David Kloba
	*/
	/// PENDING(klobad) Who should be opaque in this component?
	@SuppressWarnings("serial")
	public class JRootPane extends JComponent implements Accessible {

	private static final String uiClassID = "RootPaneUI";

	/**
	* Whether or not we should dump the stack when true double buffering
	* is disabled. Default is false.
	*/
	private static final boolean LOG_DISABLE_TRUE_DOUBLE_BUFFERING;

	/**
	* Whether or not we should ignore requests to disable true double
	* buffering. Default is false.
	*/
	private static final boolean IGNORE_DISABLE_TRUE_DOUBLE_BUFFERING;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should not provide any sort of
	* Window decorations.
	*
	* @since 1.4
	*/
	public static final int NONE = 0;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Frame.
	*
	* @since 1.4
	*/
	public static final int FRAME = 1;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog.
	*
	* @since 1.4
	*/
	public static final int PLAIN_DIALOG = 2;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog used to display an informational message.
	*
	* @since 1.4
	*/
	public static final int INFORMATION_DIALOG = 3;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog used to display an error message.
	*
	* @since 1.4
	*/
	public static final int ERROR_DIALOG = 4;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog used to display a <code>JColorChooser</code>.
	*
	* @since 1.4
	*/
	public static final int COLOR_CHOOSER_DIALOG = 5;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog used to display a <code>JFileChooser</code>.
	*
	* @since 1.4
	*/
	public static final int FILE_CHOOSER_DIALOG = 6;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog used to present a question to the user.
	*
	* @since 1.4
	*/
	public static final int QUESTION_DIALOG = 7;

	/**
	* Constant used for the windowDecorationStyle property. Indicates that
	* the <code>JRootPane</code> should provide decorations appropriate for
	* a Dialog used to display a warning message.
	*
	* @since 1.4
	*/
	public static final int WARNING_DIALOG = 8;

	private int windowDecorationStyle;

	/** The menu bar. */
	protected JMenuBar menuBar;

	/** The content pane. */
	protected Container contentPane;

	/** The layered pane that manages the menu bar and content pane. */
	protected JLayeredPane layeredPane;

	/**
	* The glass pane that overlays the menu bar and content pane,
	* so it can intercept mouse movements and such.
	*/
	protected Component glassPane;
	/**
	* The button that gets activated when the pane has the focus and
	* a UI-specific action like pressing the <b>Enter</b> key occurs.
	*/
	protected JButton defaultButton;
	/**
	* As of Java 2 platform v1.3 this unusable field is no longer used.
	* To override the default button you should replace the <code>Action</code>
	* in the <code>JRootPane</code>'s <code>ActionMap</code>. Please refer to
	* the key bindings specification for further details.
	*
	* @deprecated As of Java 2 platform v1.3.
	* @see #defaultButton
	*/
	@Deprecated
	protected DefaultAction defaultPressAction;
	/**
	* As of Java 2 platform v1.3 this unusable field is no longer used.
	* To override the default button you should replace the <code>Action</code>
	* in the <code>JRootPane</code>'s <code>ActionMap</code>. Please refer to
	* the key bindings specification for further details.
	*
	* @deprecated As of Java 2 platform v1.3.
	* @see #defaultButton
	*/
	@Deprecated
	protected DefaultAction defaultReleaseAction;

	/**
	* Whether or not true double buffering should be used. This is typically
	* true, but may be set to false in special situations. For example,
	* heavy weight popups (backed by a window) set this to false.
	*/
	boolean useTrueDoubleBuffering = true;

	static {
	LOG_DISABLE_TRUE_DOUBLE_BUFFERING =
	AccessController.doPrivileged(new GetBooleanAction(
	"swing.logDoubleBufferingDisable"));
	IGNORE_DISABLE_TRUE_DOUBLE_BUFFERING =
	AccessController.doPrivileged(new GetBooleanAction(
	"swing.ignoreDoubleBufferingDisable"));
	}

	/**
	* Creates a <code>JRootPane</code>, setting up its
	* <code>glassPane</code>, <code>layeredPane</code>,
	* and <code>contentPane</code>.
	*/
	public JRootPane() {
	setGlassPane(createGlassPane());
	setLayeredPane(createLayeredPane());
	setContentPane(createContentPane());
	setLayout(createRootLayout());
	setDoubleBuffered(true);
	updateUI();
	}

	/**
	* {@inheritDoc}
	* @since 1.6
	*/
	public void setDoubleBuffered(boolean aFlag) {
	if (isDoubleBuffered() != aFlag) {
	super.setDoubleBuffered(aFlag);
	RepaintManager.currentManager(this).doubleBufferingChanged(this);
	}
	}

	/**
	* Returns a constant identifying the type of Window decorations the
	* <code>JRootPane</code> is providing.
	*
	* @return One of <code>NONE</code>, <code>FRAME</code>,
	* <code>PLAIN_DIALOG</code>, <code>INFORMATION_DIALOG</code>,
	* <code>ERROR_DIALOG</code>, <code>COLOR_CHOOSER_DIALOG</code>,
	* <code>FILE_CHOOSER_DIALOG</code>, <code>QUESTION_DIALOG</code> or
	* <code>WARNING_DIALOG</code>.
	* @see #setWindowDecorationStyle
	* @since 1.4
	*/
	public int getWindowDecorationStyle() {
	return windowDecorationStyle;
	}

	/**
	* Sets the type of Window decorations (such as borders, widgets for
	* closing a Window, title ...) the <code>JRootPane</code> should
	* provide. The default is to provide no Window decorations
	* (<code>NONE</code>).
	* <p>
	* This is only a hint, and some look and feels may not support
	* this.
	* This is a bound property.
	*
	* @param windowDecorationStyle Constant identifying Window decorations
	* to provide.
	* @see JDialog#setDefaultLookAndFeelDecorated
	* @see JFrame#setDefaultLookAndFeelDecorated
	* @see LookAndFeel#getSupportsWindowDecorations
	* @throws IllegalArgumentException if <code>style</code> is
	* not one of: <code>NONE</code>, <code>FRAME</code>,
	* <code>PLAIN_DIALOG</code>, <code>INFORMATION_DIALOG</code>,
	* <code>ERROR_DIALOG</code>, <code>COLOR_CHOOSER_DIALOG</code>,
	* <code>FILE_CHOOSER_DIALOG</code>, <code>QUESTION_DIALOG</code>, or
	* <code>WARNING_DIALOG</code>.
	* @since 1.4
	* @beaninfo
	* bound: true
	* enum: NONE JRootPane.NONE
	* FRAME JRootPane.FRAME
	* PLAIN_DIALOG JRootPane.PLAIN_DIALOG
	* INFORMATION_DIALOG JRootPane.INFORMATION_DIALOG
	* ERROR_DIALOG JRootPane.ERROR_DIALOG
	* COLOR_CHOOSER_DIALOG JRootPane.COLOR_CHOOSER_DIALOG
	* FILE_CHOOSER_DIALOG JRootPane.FILE_CHOOSER_DIALOG
	* QUESTION_DIALOG JRootPane.QUESTION_DIALOG
	* WARNING_DIALOG JRootPane.WARNING_DIALOG
	* expert: true
	* attribute: visualUpdate true
	* description: Identifies the type of Window decorations to provide
	*/
	public void setWindowDecorationStyle(int windowDecorationStyle) {
	if (windowDecorationStyle < 0 \|\|
	windowDecorationStyle > WARNING_DIALOG) {
	throw new IllegalArgumentException("Invalid decoration style");
	}
	int oldWindowDecorationStyle = getWindowDecorationStyle();
	this.windowDecorationStyle = windowDecorationStyle;
	firePropertyChange("windowDecorationStyle",
	oldWindowDecorationStyle,
	windowDecorationStyle);
	}

	/**
	* Returns the L&F object that renders this component.
	*
	* @return <code>LabelUI</code> object
	* @since 1.3
	*/
	public RootPaneUI getUI() {
	return (RootPaneUI)ui;
	}

	/**
	* Sets the L&F object that renders this component.
	*
	* @param ui the <code>LabelUI</code> L&F object
	* @see UIDefaults#getUI
	* @beaninfo
	* bound: true
	* hidden: true
	* expert: true
	* attribute: visualUpdate true
	* description: The UI object that implements the Component's LookAndFeel.
	* @since 1.3
	*/
	public void setUI(RootPaneUI ui) {
	super.setUI(ui);
	}


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


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

	/**
	* Called by the constructor methods to create the default
	* <code>layeredPane</code>.
	* Bt default it creates a new <code>JLayeredPane</code>.
	* @return the default <code>layeredPane</code>
	*/
	protected JLayeredPane createLayeredPane() {
	JLayeredPane p = new JLayeredPane();
	p.setName(this.getName()+".layeredPane");
	return p;
	}

	/**
	* Called by the constructor methods to create the default
	* <code>contentPane</code>.
	* By default this method creates a new <code>JComponent</code> add sets a
	* <code>BorderLayout</code> as its <code>LayoutManager</code>.
	* @return the default <code>contentPane</code>
	*/
	protected Container createContentPane() {
	JComponent c = new JPanel();
	c.setName(this.getName()+".contentPane");
	c.setLayout(new BorderLayout() {
	/* This BorderLayout subclass maps a null constraint to CENTER.
	* Although the reference BorderLayout also does this, some VMs
	* throw an IllegalArgumentException.
	*/
	public void addLayoutComponent(Component comp, Object constraints) {
	if (constraints == null) {
	constraints = BorderLayout.CENTER;
	}
	super.addLayoutComponent(comp, constraints);
	}
	});
	return c;
	}

	/**
	* Called by the constructor methods to create the default
	* <code>glassPane</code>.
	* By default this method creates a new <code>JComponent</code>
	* with visibility set to false.
	* @return the default <code>glassPane</code>
	*/
	protected Component createGlassPane() {
	JComponent c = new JPanel();
	c.setName(this.getName()+".glassPane");
	c.setVisible(false);
	((JPanel)c).setOpaque(false);
	return c;
	}

	/**
	* Called by the constructor methods to create the default
	* <code>layoutManager</code>.
	* @return the default <code>layoutManager</code>.
	*/
	protected LayoutManager createRootLayout() {
	return new RootLayout();
	}

	/**
	* Adds or changes the menu bar used in the layered pane.
	* @param menu the <code>JMenuBar</code> to add
	*/
	public void setJMenuBar(JMenuBar menu) {
	if(menuBar != null && menuBar.getParent() == layeredPane)
	layeredPane.remove(menuBar);
	menuBar = menu;

	if(menuBar != null)
	layeredPane.add(menuBar, JLayeredPane.FRAME_CONTENT_LAYER);
	}

	/**
	* Specifies the menu bar value.
	* @deprecated As of Swing version 1.0.3
	* replaced by <code>setJMenuBar(JMenuBar menu)</code>.
	* @param menu the <code>JMenuBar</code> to add.
	*/
	@Deprecated
	public void setMenuBar(JMenuBar menu){
	if(menuBar != null && menuBar.getParent() == layeredPane)
	layeredPane.remove(menuBar);
	menuBar = menu;

	if(menuBar != null)
	layeredPane.add(menuBar, JLayeredPane.FRAME_CONTENT_LAYER);
	}

	/**
	* Returns the menu bar from the layered pane.
	* @return the <code>JMenuBar</code> used in the pane
	*/
	public JMenuBar getJMenuBar() { return menuBar; }

	/**
	* Returns the menu bar value.
	* @deprecated As of Swing version 1.0.3
	* replaced by <code>getJMenuBar()</code>.
	* @return the <code>JMenuBar</code> used in the pane
	*/
	@Deprecated
	public JMenuBar getMenuBar() { return menuBar; }

	/**
	* Sets the content pane -- the container that holds the components
	* parented by the root pane.
	* <p>
	* Swing's painting architecture requires an opaque <code>JComponent</code>
	* in the containment hierarchy. This is typically provided by the
	* content pane. If you replace the content pane it is recommended you
	* replace it with an opaque <code>JComponent</code>.
	*
	* @param content the <code>Container</code> to use for component-contents
	* @exception java.awt.IllegalComponentStateException (a runtime
	* exception) if the content pane parameter is <code>null</code>
	*/
	public void setContentPane(Container content) {
	if(content == null)
	throw new IllegalComponentStateException("contentPane cannot be set to null.");
	if(contentPane != null && contentPane.getParent() == layeredPane)
	layeredPane.remove(contentPane);
	contentPane = content;

	layeredPane.add(contentPane, JLayeredPane.FRAME_CONTENT_LAYER);
	}

	/**
	* Returns the content pane -- the container that holds the components
	* parented by the root pane.
	*
	* @return the <code>Container</code> that holds the component-contents
	*/
	public Container getContentPane() { return contentPane; }

	// PENDING(klobad) Should this reparent the contentPane and MenuBar?
	/**
	* Sets the layered pane for the root pane. The layered pane
	* typically holds a content pane and an optional <code>JMenuBar</code>.
	*
	* @param layered the <code>JLayeredPane</code> to use
	* @exception java.awt.IllegalComponentStateException (a runtime
	* exception) if the layered pane parameter is <code>null</code>
	*/
	public void setLayeredPane(JLayeredPane layered) {
	if(layered == null)
	throw new IllegalComponentStateException("layeredPane cannot be set to null.");
	if(layeredPane != null && layeredPane.getParent() == this)
	this.remove(layeredPane);
	layeredPane = layered;

	this.add(layeredPane, -1);
	}
	/**
	* Gets the layered pane used by the root pane. The layered pane
	* typically holds a content pane and an optional <code>JMenuBar</code>.
	*
	* @return the <code>JLayeredPane</code> currently in use
	*/
	public JLayeredPane getLayeredPane() { return layeredPane; }

	/**
	* Sets a specified <code>Component</code> to be the glass pane for this
	* root pane. The glass pane should normally be a lightweight,
	* transparent component, because it will be made visible when
	* ever the root pane needs to grab input events.
	* <p>
	* The new glass pane's visibility is changed to match that of
	* the current glass pane. An implication of this is that care
	* must be taken when you want to replace the glass pane and
	* make it visible. Either of the following will work:
	* <pre>
	* root.setGlassPane(newGlassPane);
	* newGlassPane.setVisible(true);
	* </pre>
	* or:
	* <pre>
	* root.getGlassPane().setVisible(true);
	* root.setGlassPane(newGlassPane);
	* </pre>
	*
	* @param glass the <code>Component</code> to use as the glass pane
	* for this <code>JRootPane</code>
	* @exception NullPointerException if the <code>glass</code> parameter is
	* <code>null</code>
	*/
	public void setGlassPane(Component glass) {
	if (glass == null) {
	throw new NullPointerException("glassPane cannot be set to null.");
	}

	AWTAccessor.getComponentAccessor().setMixingCutoutShape(glass,
	new Rectangle());

	boolean visible = false;
	if (glassPane != null && glassPane.getParent() == this) {
	this.remove(glassPane);
	visible = glassPane.isVisible();
	}

	glass.setVisible(visible);
	glassPane = glass;
	this.add(glassPane, 0);
	if (visible) {
	repaint();
	}
	}

	/**
	* Returns the current glass pane for this <code>JRootPane</code>.
	* @return the current glass pane
	* @see #setGlassPane
	*/
	public Component getGlassPane() {
	return glassPane;
	}

	/**
	* If a descendant of this <code>JRootPane</code> calls
	* <code>revalidate</code>, validate from here on down.
	*<p>
	* Deferred requests to layout a component and its descendents again.
	* For example, calls to <code>revalidate</code>, are pushed upwards to
	* either a <code>JRootPane</code> or a <code>JScrollPane</code>
	* because both classes override <code>isValidateRoot</code> to return true.
	*
	* @see JComponent#isValidateRoot
	* @see java.awt.Container#isValidateRoot
	* @return true
	*/
	@Override
	public boolean isValidateRoot() {
	return true;
	}

	/**
	* The <code>glassPane</code> and <code>contentPane</code>
	* have the same bounds, which means <code>JRootPane</code>
	* does not tiles its children and this should return false.
	* On the other hand, the <code>glassPane</code>
	* is normally not visible, and so this can return true if the
	* <code>glassPane</code> isn't visible. Therefore, the
	* return value here depends upon the visibility of the
	* <code>glassPane</code>.
	*
	* @return true if this component's children don't overlap
	*/
	public boolean isOptimizedDrawingEnabled() {
	return !glassPane.isVisible();
	}

	/**
	* {@inheritDoc}
	*/
	public void addNotify() {
	super.addNotify();
	enableEvents(AWTEvent.KEY_EVENT_MASK);
	}

	/**
	* {@inheritDoc}
	*/
	public void removeNotify() {
	super.removeNotify();
	}


	/**
	* Sets the <code>defaultButton</code> property,
	* which determines the current default button for this <code>JRootPane</code>.
	* The default button is the button which will be activated
	* when a UI-defined activation event (typically the <b>Enter</b> key)
	* occurs in the root pane regardless of whether or not the button
	* has keyboard focus (unless there is another component within
	* the root pane which consumes the activation event,
	* such as a <code>JTextPane</code>).
	* For default activation to work, the button must be an enabled
	* descendent of the root pane when activation occurs.
	* To remove a default button from this root pane, set this
	* property to <code>null</code>.
	*
	* @see JButton#isDefaultButton
	* @param defaultButton the <code>JButton</code> which is to be the default button
	*
	* @beaninfo
	* description: The button activated by default in this root pane
	*/
	public void setDefaultButton(JButton defaultButton) {
	JButton oldDefault = this.defaultButton;

	if (oldDefault != defaultButton) {
	this.defaultButton = defaultButton;

	if (oldDefault != null) {
	oldDefault.repaint();
	}
	if (defaultButton != null) {
	defaultButton.repaint();
	}
	}

	firePropertyChange("defaultButton", oldDefault, defaultButton);
	}

	/**
	* Returns the value of the <code>defaultButton</code> property.
	* @return the <code>JButton</code> which is currently the default button
	* @see #setDefaultButton
	*/
	public JButton getDefaultButton() {
	return defaultButton;
	}

	final void setUseTrueDoubleBuffering(boolean useTrueDoubleBuffering) {
	this.useTrueDoubleBuffering = useTrueDoubleBuffering;
	}

	final boolean getUseTrueDoubleBuffering() {
	return useTrueDoubleBuffering;
	}

	final void disableTrueDoubleBuffering() {
	if (useTrueDoubleBuffering) {
	if (!IGNORE_DISABLE_TRUE_DOUBLE_BUFFERING) {
	if (LOG_DISABLE_TRUE_DOUBLE_BUFFERING) {
	System.out.println("Disabling true double buffering for " +
	this);
	Thread.dumpStack();
	}
	useTrueDoubleBuffering = false;
	RepaintManager.currentManager(this).
	doubleBufferingChanged(this);
	}
	}
	}

	@SuppressWarnings("serial")
	static class DefaultAction extends AbstractAction {
	JButton owner;
	JRootPane root;
	boolean press;
	DefaultAction(JRootPane root, boolean press) {
	this.root = root;
	this.press = press;
	}
	public void setOwner(JButton owner) {
	this.owner = owner;
	}
	public void actionPerformed(ActionEvent e) {
	if (owner != null && SwingUtilities.getRootPane(owner) == root) {
	ButtonModel model = owner.getModel();
	if (press) {
	model.setArmed(true);
	model.setPressed(true);
	} else {
	model.setPressed(false);
	}
	}
	}
	public boolean isEnabled() {
	return owner.getModel().isEnabled();
	}
	}


	/**
	* Overridden to enforce the position of the glass component as
	* the zero child.
	*
	* @param comp the component to be enhanced
	* @param constraints the constraints to be respected
	* @param index the index
	*/
	protected void addImpl(Component comp, Object constraints, int index) {
	super.addImpl(comp, constraints, index);

	/// We are making sure the glassPane is on top.
	if(glassPane != null
	&& glassPane.getParent() == this
	&& getComponent(0) != glassPane) {
	add(glassPane, 0);
	}
	}


	///////////////////////////////////////////////////////////////////////////////
	//// Begin Inner Classes
	///////////////////////////////////////////////////////////////////////////////


	/**
	* A custom layout manager that is responsible for the layout of
	* layeredPane, glassPane, and menuBar.
	* <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 RootLayout implements LayoutManager2, Serializable
	{
	/**
	* Returns the amount of space the layout would like to have.
	*
	* @param parent the Container for which this layout manager
	* is being used
	* @return a Dimension object containing the layout's preferred size
	*/
	public Dimension preferredLayoutSize(Container parent) {
	Dimension rd, mbd;
	Insets i = getInsets();

	if(contentPane != null) {
	rd = contentPane.getPreferredSize();
	} else {
	rd = parent.getSize();
	}
	if(menuBar != null && menuBar.isVisible()) {
	mbd = menuBar.getPreferredSize();
	} else {
	mbd = new Dimension(0, 0);
	}
	return new Dimension(Math.max(rd.width, mbd.width) + i.left + i.right,
	rd.height + mbd.height + i.top + i.bottom);
	}

	/**
	* Returns the minimum amount of space the layout needs.
	*
	* @param parent the Container for which this layout manager
	* is being used
	* @return a Dimension object containing the layout's minimum size
	*/
	public Dimension minimumLayoutSize(Container parent) {
	Dimension rd, mbd;
	Insets i = getInsets();
	if(contentPane != null) {
	rd = contentPane.getMinimumSize();
	} else {
	rd = parent.getSize();
	}
	if(menuBar != null && menuBar.isVisible()) {
	mbd = menuBar.getMinimumSize();
	} else {
	mbd = new Dimension(0, 0);
	}
	return new Dimension(Math.max(rd.width, mbd.width) + i.left + i.right,
	rd.height + mbd.height + i.top + i.bottom);
	}

	/**
	* Returns the maximum amount of space the layout can use.
	*
	* @param target the Container for which this layout manager
	* is being used
	* @return a Dimension object containing the layout's maximum size
	*/
	public Dimension maximumLayoutSize(Container target) {
	Dimension rd, mbd;
	Insets i = getInsets();
	if(menuBar != null && menuBar.isVisible()) {
	mbd = menuBar.getMaximumSize();
	} else {
	mbd = new Dimension(0, 0);
	}
	if(contentPane != null) {
	rd = contentPane.getMaximumSize();
	} else {
	// This is silly, but should stop an overflow error
	rd = new Dimension(Integer.MAX_VALUE,
	Integer.MAX_VALUE - i.top - i.bottom - mbd.height - 1);
	}
	return new Dimension(Math.min(rd.width, mbd.width) + i.left + i.right,
	rd.height + mbd.height + i.top + i.bottom);
	}

	/**
	* Instructs the layout manager to perform the layout for the specified
	* container.
	*
	* @param parent the Container for which this layout manager
	* is being used
	*/
	public void layoutContainer(Container parent) {
	Rectangle b = parent.getBounds();
	Insets i = getInsets();
	int contentY = 0;
	int w = b.width - i.right - i.left;
	int h = b.height - i.top - i.bottom;

	if(layeredPane != null) {
	layeredPane.setBounds(i.left, i.top, w, h);
	}
	if(glassPane != null) {
	glassPane.setBounds(i.left, i.top, w, h);
	}
	// Note: This is laying out the children in the layeredPane,
	// technically, these are not our children.
	if(menuBar != null && menuBar.isVisible()) {
	Dimension mbd = menuBar.getPreferredSize();
	menuBar.setBounds(0, 0, w, mbd.height);
	contentY += mbd.height;
	}
	if(contentPane != null) {
	contentPane.setBounds(0, contentY, w, h - contentY);
	}
	}

	public void addLayoutComponent(String name, Component comp) {}
	public void removeLayoutComponent(Component comp) {}
	public void addLayoutComponent(Component comp, Object constraints) {}
	public float getLayoutAlignmentX(Container target) { return 0.0f; }
	public float getLayoutAlignmentY(Container target) { return 0.0f; }
	public void invalidateLayout(Container target) {}
	}

	/**
	* Returns a string representation of this <code>JRootPane</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>JRootPane</code>.
	*/
	protected String paramString() {
	return super.paramString();
	}

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

	/**
	* Gets the <code>AccessibleContext</code> associated with this
	* <code>JRootPane</code>. For root panes, the
	* <code>AccessibleContext</code> takes the form of an
	* <code>AccessibleJRootPane</code>.
	* A new <code>AccessibleJRootPane</code> instance is created if necessary.
	*
	* @return an <code>AccessibleJRootPane</code> that serves as the
	* <code>AccessibleContext</code> of this <code>JRootPane</code>
	*/
	public AccessibleContext getAccessibleContext() {
	if (accessibleContext == null) {
	accessibleContext = new AccessibleJRootPane();
	}
	return accessibleContext;
	}

	/**
	* This class implements accessibility support for the
	* <code>JRootPane</code> class. It provides an implementation of the
	* Java Accessibility API appropriate to root pane 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 AccessibleJRootPane extends AccessibleJComponent {
	/**
	* Get the role of this object.
	*
	* @return an instance of AccessibleRole describing the role of
	* the object
	*/
	public AccessibleRole getAccessibleRole() {
	return AccessibleRole.ROOT_PANE;
	}

	/**
	* Returns the number of accessible children of the object.
	*
	* @return the number of accessible children of the object.
	*/
	public int getAccessibleChildrenCount() {
	return super.getAccessibleChildrenCount();
	}

	/**
	* Returns the specified Accessible child of the object. The Accessible
	* children of an Accessible object are zero-based, so the first child
	* of an Accessible child is at index 0, the second child is at index 1,
	* and so on.
	*
	* @param i zero-based index of child
	* @return the Accessible child of the object
	* @see #getAccessibleChildrenCount
	*/
	public Accessible getAccessibleChild(int i) {
	return super.getAccessibleChild(i);
	}
	} // inner class AccessibleJRootPane
	}

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