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	/*
	* Copyright (c) 1999, 2011, 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 sun.awt.ModalExclude;
	import sun.awt.SunToolkit;

	/**
	* Popups are used to display a <code>Component</code> to the user, typically
	* on top of all the other <code>Component</code>s in a particular containment
	* hierarchy. <code>Popup</code>s have a very small life cycle. Once you
	* have obtained a <code>Popup</code>, and hidden it (invoked the
	* <code>hide</code> method), you should no longer
	* invoke any methods on it. This allows the <code>PopupFactory</code> to cache
	* <code>Popup</code>s for later use.
	* <p>
	* The general contract is that if you need to change the size of the
	* <code>Component</code>, or location of the <code>Popup</code>, you should
	* obtain a new <code>Popup</code>.
	* <p>
	* <code>Popup</code> does not descend from <code>Component</code>, rather
	* implementations of <code>Popup</code> are responsible for creating
	* and maintaining their own <code>Component</code>s to render the
	* requested <code>Component</code> to the user.
	* <p>
	* You typically do not explicitly create an instance of <code>Popup</code>,
	* instead obtain one from a <code>PopupFactory</code>.
	*
	* @see PopupFactory
	*
	* @since 1.4
	*/
	public class Popup {
	/**
	* The Component representing the Popup.
	*/
	private Component component;

	/**
	* Creates a <code>Popup</code> for the Component <code>owner</code>
	* containing the Component <code>contents</code>. <code>owner</code>
	* is used to determine which <code>Window</code> the new
	* <code>Popup</code> will parent the <code>Component</code> the
	* <code>Popup</code> creates to.
	* A null <code>owner</code> implies there is no valid parent.
	* <code>x</code> and
	* <code>y</code> specify the preferred initial location to place
	* the <code>Popup</code> at. Based on screen size, or other paramaters,
	* the <code>Popup</code> may not display at <code>x</code> and
	* <code>y</code>.
	*
	* @param owner Component mouse coordinates are relative to, may be null
	* @param contents Contents of the Popup
	* @param x Initial x screen coordinate
	* @param y Initial y screen coordinate
	* @exception IllegalArgumentException if contents is null
	*/
	protected Popup(Component owner, Component contents, int x, int y) {
	this();
	if (contents == null) {
	throw new IllegalArgumentException("Contents must be non-null");
	}
	reset(owner, contents, x, y);
	}

	/**
	* Creates a <code>Popup</code>. This is provided for subclasses.
	*/
	protected Popup() {
	}

	/**
	* Makes the <code>Popup</code> visible. If the <code>Popup</code> is
	* currently visible, this has no effect.
	*/

	@SuppressWarnings("deprecation")
	public void show() {
	Component component = getComponent();

	if (component != null) {
	component.show();
	}
	}

	/**
	* Hides and disposes of the <code>Popup</code>. Once a <code>Popup</code>
	* has been disposed you should no longer invoke methods on it. A
	* <code>dispose</code>d <code>Popup</code> may be reclaimed and later used
	* based on the <code>PopupFactory</code>. As such, if you invoke methods
	* on a <code>disposed</code> <code>Popup</code>, indeterminate
	* behavior will result.
	*/

	@SuppressWarnings("deprecation")
	public void hide() {
	Component component = getComponent();

	if (component instanceof JWindow) {
	component.hide();
	((JWindow)component).getContentPane().removeAll();
	}
	dispose();
	}

	/**
	* Frees any resources the <code>Popup</code> may be holding onto.
	*/
	void dispose() {
	Component component = getComponent();
	Window window = SwingUtilities.getWindowAncestor(component);

	if (component instanceof JWindow) {
	((Window)component).dispose();
	component = null;
	}
	// If our parent is a DefaultFrame, we need to dispose it, too.
	if (window instanceof DefaultFrame) {
	window.dispose();
	}
	}

	/**
	* Resets the <code>Popup</code> to an initial state.
	*/
	void reset(Component owner, Component contents, int ownerX, int ownerY) {
	if (getComponent() == null) {
	component = createComponent(owner);
	}

	Component c = getComponent();

	if (c instanceof JWindow) {
	JWindow component = (JWindow)getComponent();

	component.setLocation(ownerX, ownerY);
	component.getContentPane().add(contents, BorderLayout.CENTER);
	component.invalidate();
	component.validate();
	if(component.isVisible()) {
	// Do not call pack() if window is not visible to
	// avoid early native peer creation
	pack();
	}
	}
	}


	/**
	* Causes the <code>Popup</code> to be sized to fit the preferred size
	* of the <code>Component</code> it contains.
	*/
	void pack() {
	Component component = getComponent();

	if (component instanceof Window) {
	((Window)component).pack();
	}
	}

	/**
	* Returns the <code>Window</code> to use as the parent of the
	* <code>Window</code> created for the <code>Popup</code>. This creates
	* a new <code>DefaultFrame</code>, if necessary.
	*/
	private Window getParentWindow(Component owner) {
	Window window = null;

	if (owner instanceof Window) {
	window = (Window)owner;
	}
	else if (owner != null) {
	window = SwingUtilities.getWindowAncestor(owner);
	}
	if (window == null) {
	window = new DefaultFrame();
	}
	return window;
	}

	/**
	* Creates the Component to use as the parent of the <code>Popup</code>.
	* The default implementation creates a <code>Window</code>, subclasses
	* should override.
	*/
	Component createComponent(Component owner) {
	if (GraphicsEnvironment.isHeadless()) {
	// Generally not useful, bail.
	return null;
	}
	return new HeavyWeightWindow(getParentWindow(owner));
	}

	/**
	* Returns the <code>Component</code> returned from
	* <code>createComponent</code> that will hold the <code>Popup</code>.
	*/
	Component getComponent() {
	return component;
	}


	/**
	* Component used to house window.
	*/
	static class HeavyWeightWindow extends JWindow implements ModalExclude {
	HeavyWeightWindow(Window parent) {
	super(parent);
	setFocusableWindowState(false);
	setType(Window.Type.POPUP);

	// Popups are typically transient and most likely won't benefit
	// from true double buffering. Turn it off here.
	getRootPane().setUseTrueDoubleBuffering(false);
	// Try to set "always-on-top" for the popup window.
	// Applets usually don't have sufficient permissions to do it.
	// In this case simply ignore the exception.
	try {
	setAlwaysOnTop(true);
	} catch (SecurityException se) {
	// setAlwaysOnTop is restricted,
	// the exception is ignored
	}
	}

	public void update(Graphics g) {
	paint(g);
	}

	public void show() {
	this.pack();
	if (getWidth() > 0 && getHeight() > 0) {
	super.show();
	}
	}
	}


	/**
	* Used if no valid Window ancestor of the supplied owner is found.
	* <p>
	* PopupFactory uses this as a way to know when the Popup shouldn't
	* be cached based on the Window.
	*/
	static class DefaultFrame extends Frame {
	}
	}

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