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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.*;
	import java.awt.event.*;
	import java.applet.Applet;
	import java.beans.PropertyChangeListener;
	import java.util.Locale;
	import java.util.Vector;
	import java.io.Serializable;
	import javax.accessibility.*;

	/**
	* An extended version of <code>java.applet.Applet</code> that adds support for
	* the JFC/Swing component architecture.
	* You can find task-oriented documentation about using <code>JApplet</code>
	* in <em>The Java Tutorial</em>,
	* in the section
	* <a
	href="https://docs.oracle.com/javase/tutorial/uiswing/components/applet.html">How to Make Applets</a>.
	* <p>
	* The <code>JApplet</code> class is slightly incompatible with
	* <code>java.applet.Applet</code>. <code>JApplet</code> contains a
	* <code>JRootPane</code> as its only child. The <code>contentPane</code>
	* should be the parent of any children of the <code>JApplet</code>.
	* As a convenience, the {@code add}, {@code remove}, and {@code setLayout}
	* methods of this class are overridden, so that they delegate calls
	* to the corresponding methods of the {@code ContentPane}.
	* For example, you can add a child component to an applet as follows:
	* <pre>
	* applet.add(child);
	* </pre>
	*
	* And the child will be added to the <code>contentPane</code>.
	* The <code>contentPane</code> will always be non-<code>null</code>.
	* Attempting to set it to <code>null</code> will cause the
	* <code>JApplet</code> to throw an exception. The default
	* <code>contentPane</code> will have a <code>BorderLayout</code>
	* manager set on it.
	* Refer to {@link javax.swing.RootPaneContainer}
	* for details on adding, removing and setting the <code>LayoutManager</code>
	* of a <code>JApplet</code>.
	* <p>
	* Please see the <code>JRootPane</code> documentation for a
	* complete description of the <code>contentPane</code>, <code>glassPane</code>,
	* and <code>layeredPane</code> properties.
	* <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 javax.swing.RootPaneContainer
	* @beaninfo
	* attribute: isContainer true
	* attribute: containerDelegate getContentPane
	* description: Swing's Applet subclass.
	*
	* @author Arnaud Weber
	*/
	public class JApplet extends Applet implements Accessible,
	RootPaneContainer,
	TransferHandler.HasGetTransferHandler
	{
	/**
	* @see #getRootPane
	* @see #setRootPane
	*/
	protected JRootPane rootPane;

	/**
	* If true then calls to <code>add</code> and <code>setLayout</code>
	* will be forwarded to the <code>contentPane</code>. This is initially
	* false, but is set to true when the <code>JApplet</code> is constructed.
	*
	* @see #isRootPaneCheckingEnabled
	* @see #setRootPaneCheckingEnabled
	* @see javax.swing.RootPaneContainer
	*/
	protected boolean rootPaneCheckingEnabled = false;

	/**
	* The <code>TransferHandler</code> for this applet.
	*/
	private TransferHandler transferHandler;

	/**
	* Creates a swing applet instance.
	* <p>
	* This constructor sets the component's locale property to the value
	* returned by <code>JComponent.getDefaultLocale</code>.
	*
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true.
	* @see java.awt.GraphicsEnvironment#isHeadless
	* @see JComponent#getDefaultLocale
	*/
	public JApplet() throws HeadlessException {
	super();
	// Check the timerQ and restart if necessary.
	TimerQueue q = TimerQueue.sharedInstance();
	if(q != null) {
	q.startIfNeeded();
	}

	/* Workaround for bug 4155072. The shared double buffer image
	* may hang on to a reference to this applet; unfortunately
	* Image.getGraphics() will continue to call JApplet.getForeground()
	* and getBackground() even after this applet has been destroyed.
	* So we ensure that these properties are non-null here.
	*/
	setForeground(Color.black);
	setBackground(Color.white);

	setLocale( JComponent.getDefaultLocale() );
	setLayout(new BorderLayout());
	setRootPane(createRootPane());
	setRootPaneCheckingEnabled(true);

	setFocusTraversalPolicyProvider(true);
	sun.awt.SunToolkit.checkAndSetPolicy(this);

	enableEvents(AWTEvent.KEY_EVENT_MASK);
	}


	/** Called by the constructor methods to create the default rootPane. */
	protected JRootPane createRootPane() {
	JRootPane rp = new JRootPane();
	// NOTE: this uses setOpaque vs LookAndFeel.installProperty as there
	// is NO reason for the RootPane not to be opaque. For painting to
	// work the contentPane must be opaque, therefor the RootPane can
	// also be opaque.
	rp.setOpaque(true);
	return rp;
	}

	/**
	* Sets the {@code transferHandler} property, which is a mechanism to
	* support transfer of data into this component. Use {@code null}
	* if the component does not support data transfer operations.
	* <p>
	* If the system property {@code suppressSwingDropSupport} is {@code false}
	* (the default) and the current drop target on this component is either
	* {@code null} or not a user-set drop target, this method will change the
	* drop target as follows: If {@code newHandler} is {@code null} it will
	* clear the drop target. If not {@code null} it will install a new
	* {@code DropTarget}.
	* <p>
	* Note: When used with {@code JApplet}, {@code TransferHandler} only
	* provides data import capability, as the data export related methods
	* are currently typed to {@code JComponent}.
	* <p>
	* Please see
	* <a href="https://docs.oracle.com/javase/tutorial/uiswing/dnd/index.html">
	* How to Use Drag and Drop and Data Transfer</a>, a section in
	* <em>The Java Tutorial</em>, for more information.
	*
	* @param newHandler the new {@code TransferHandler}
	*
	* @see TransferHandler
	* @see #getTransferHandler
	* @see java.awt.Component#setDropTarget
	* @since 1.6
	*
	* @beaninfo
	* bound: true
	* hidden: true
	* description: Mechanism for transfer of data into the component
	*/
	public void setTransferHandler(TransferHandler newHandler) {
	TransferHandler oldHandler = transferHandler;
	transferHandler = newHandler;
	SwingUtilities.installSwingDropTargetAsNecessary(this, transferHandler);
	firePropertyChange("transferHandler", oldHandler, newHandler);
	}

	/**
	* Gets the <code>transferHandler</code> property.
	*
	* @return the value of the <code>transferHandler</code> property
	*
	* @see TransferHandler
	* @see #setTransferHandler
	* @since 1.6
	*/
	public TransferHandler getTransferHandler() {
	return transferHandler;
	}

	/**
	* Just calls <code>paint(g)</code>. This method was overridden to
	* prevent an unnecessary call to clear the background.
	*/
	public void update(Graphics g) {
	paint(g);
	}

	/**
	* Sets the menubar for this applet.
	* @param menuBar the menubar being placed in the applet
	*
	* @see #getJMenuBar
	*
	* @beaninfo
	* hidden: true
	* description: The menubar for accessing pulldown menus from this applet.
	*/
	public void setJMenuBar(JMenuBar menuBar) {
	getRootPane().setMenuBar(menuBar);
	}

	/**
	* Returns the menubar set on this applet.
	*
	* @see #setJMenuBar
	*/
	public JMenuBar getJMenuBar() {
	return getRootPane().getMenuBar();
	}


	/**
	* Returns whether calls to <code>add</code> and
	* <code>setLayout</code> are forwarded to the <code>contentPane</code>.
	*
	* @return true if <code>add</code> and <code>setLayout</code>
	* are forwarded; false otherwise
	*
	* @see #addImpl
	* @see #setLayout
	* @see #setRootPaneCheckingEnabled
	* @see javax.swing.RootPaneContainer
	*/
	protected boolean isRootPaneCheckingEnabled() {
	return rootPaneCheckingEnabled;
	}


	/**
	* Sets whether calls to <code>add</code> and
	* <code>setLayout</code> are forwarded to the <code>contentPane</code>.
	*
	* @param enabled true if <code>add</code> and <code>setLayout</code>
	* are forwarded, false if they should operate directly on the
	* <code>JApplet</code>.
	*
	* @see #addImpl
	* @see #setLayout
	* @see #isRootPaneCheckingEnabled
	* @see javax.swing.RootPaneContainer
	* @beaninfo
	* hidden: true
	* description: Whether the add and setLayout methods are forwarded
	*/
	protected void setRootPaneCheckingEnabled(boolean enabled) {
	rootPaneCheckingEnabled = enabled;
	}


	/**
	* Adds the specified child <code>Component</code>.
	* This method is overridden to conditionally forward calls to the
	* <code>contentPane</code>.
	* By default, children are added to the <code>contentPane</code> instead
	* of the frame, refer to {@link javax.swing.RootPaneContainer} for
	* details.
	*
	* @param comp the component to be enhanced
	* @param constraints the constraints to be respected
	* @param index the index
	* @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
	*
	* @see #setRootPaneCheckingEnabled
	* @see javax.swing.RootPaneContainer
	*/
	protected void addImpl(Component comp, Object constraints, int index)
	{
	if(isRootPaneCheckingEnabled()) {
	getContentPane().add(comp, constraints, index);
	}
	else {
	super.addImpl(comp, constraints, index);
	}
	}

	/**
	* Removes the specified component from the container. If
	* <code>comp</code> is not the <code>rootPane</code>, this will forward
	* the call to the <code>contentPane</code>. This will do nothing if
	* <code>comp</code> is not a child of the <code>JFrame</code> or
	* <code>contentPane</code>.
	*
	* @param comp the component to be removed
	* @throws NullPointerException if <code>comp</code> is null
	* @see #add
	* @see javax.swing.RootPaneContainer
	*/
	public void remove(Component comp) {
	if (comp == rootPane) {
	super.remove(comp);
	} else {
	getContentPane().remove(comp);
	}
	}


	/**
	* Sets the <code>LayoutManager</code>.
	* Overridden to conditionally forward the call to the
	* <code>contentPane</code>.
	* Refer to {@link javax.swing.RootPaneContainer} for
	* more information.
	*
	* @param manager the <code>LayoutManager</code>
	* @see #setRootPaneCheckingEnabled
	* @see javax.swing.RootPaneContainer
	*/
	public void setLayout(LayoutManager manager) {
	if(isRootPaneCheckingEnabled()) {
	getContentPane().setLayout(manager);
	}
	else {
	super.setLayout(manager);
	}
	}


	/**
	* Returns the rootPane object for this applet.
	*
	* @see #setRootPane
	* @see RootPaneContainer#getRootPane
	*/
	public JRootPane getRootPane() {
	return rootPane;
	}


	/**
	* Sets the rootPane property. This method is called by the constructor.
	* @param root the rootPane object for this applet
	*
	* @see #getRootPane
	*
	* @beaninfo
	* hidden: true
	* description: the RootPane object for this applet.
	*/
	protected void setRootPane(JRootPane root) {
	if(rootPane != null) {
	remove(rootPane);
	}
	rootPane = root;
	if(rootPane != null) {
	boolean checkingEnabled = isRootPaneCheckingEnabled();
	try {
	setRootPaneCheckingEnabled(false);
	add(rootPane, BorderLayout.CENTER);
	}
	finally {
	setRootPaneCheckingEnabled(checkingEnabled);
	}
	}
	}


	/**
	* Returns the contentPane object for this applet.
	*
	* @see #setContentPane
	* @see RootPaneContainer#getContentPane
	*/
	public Container getContentPane() {
	return getRootPane().getContentPane();
	}

	/**
	* Sets the contentPane property. This method is called by the constructor.
	* @param contentPane the contentPane object for this applet
	*
	* @exception java.awt.IllegalComponentStateException (a runtime
	* exception) if the content pane parameter is null
	* @see #getContentPane
	* @see RootPaneContainer#setContentPane
	*
	* @beaninfo
	* hidden: true
	* description: The client area of the applet where child
	* components are normally inserted.
	*/
	public void setContentPane(Container contentPane) {
	getRootPane().setContentPane(contentPane);
	}

	/**
	* Returns the layeredPane object for this applet.
	*
	* @exception java.awt.IllegalComponentStateException (a runtime
	* exception) if the layered pane parameter is null
	* @see #setLayeredPane
	* @see RootPaneContainer#getLayeredPane
	*/
	public JLayeredPane getLayeredPane() {
	return getRootPane().getLayeredPane();
	}

	/**
	* Sets the layeredPane property. This method is called by the constructor.
	* @param layeredPane the layeredPane object for this applet
	*
	* @see #getLayeredPane
	* @see RootPaneContainer#setLayeredPane
	*
	* @beaninfo
	* hidden: true
	* description: The pane which holds the various applet layers.
	*/
	public void setLayeredPane(JLayeredPane layeredPane) {
	getRootPane().setLayeredPane(layeredPane);
	}

	/**
	* Returns the glassPane object for this applet.
	*
	* @see #setGlassPane
	* @see RootPaneContainer#getGlassPane
	*/
	public Component getGlassPane() {
	return getRootPane().getGlassPane();
	}

	/**
	* Sets the glassPane property.
	* This method is called by the constructor.
	* @param glassPane the glassPane object for this applet
	*
	* @see #getGlassPane
	* @see RootPaneContainer#setGlassPane
	*
	* @beaninfo
	* hidden: true
	* description: A transparent pane used for menu rendering.
	*/
	public void setGlassPane(Component glassPane) {
	getRootPane().setGlassPane(glassPane);
	}

	/**
	* {@inheritDoc}
	*
	* @since 1.6
	*/
	public Graphics getGraphics() {
	JComponent.getGraphicsInvoked(this);
	return super.getGraphics();
	}

	/**
	* Repaints the specified rectangle of this component within
	* <code>time</code> milliseconds. Refer to <code>RepaintManager</code>
	* for details on how the repaint is handled.
	*
	* @param time maximum time in milliseconds before update
	* @param x the <i>x</i> coordinate
	* @param y the <i>y</i> coordinate
	* @param width the width
	* @param height the height
	* @see RepaintManager
	* @since 1.6
	*/
	public void repaint(long time, int x, int y, int width, int height) {
	if (RepaintManager.HANDLE_TOP_LEVEL_PAINT) {
	RepaintManager.currentManager(this).addDirtyRegion(
	this, x, y, width, height);
	}
	else {
	super.repaint(time, x, y, width, height);
	}
	}

	/**
	* Returns a string representation of this JApplet. 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 JApplet.
	*/
	protected String paramString() {
	String rootPaneString = (rootPane != null ?
	rootPane.toString() : "");
	String rootPaneCheckingEnabledString = (rootPaneCheckingEnabled ?
	"true" : "false");

	return super.paramString() +
	",rootPane=" + rootPaneString +
	",rootPaneCheckingEnabled=" + rootPaneCheckingEnabledString;
	}



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

	protected AccessibleContext accessibleContext = null;

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

	/**
	* This class implements accessibility support for the
	* <code>JApplet</code> class.
	*/
	protected class AccessibleJApplet extends AccessibleApplet {
	// everything moved to new parent, AccessibleApplet
	}
	}

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