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	/*
	* Copyright (c) 1995, 2007, 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 javax.accessibility.*;

	/**
	* <code>Panel</code> is the simplest container class. A panel
	* provides space in which an application can attach any other
	* component, including other panels.
	* <p>
	* The default layout manager for a panel is the
	* <code>FlowLayout</code> layout manager.
	*
	* @author Sami Shaio
	* @see java.awt.FlowLayout
	* @since JDK1.0
	*/
	public class Panel extends Container implements Accessible {
	private static final String base = "panel";
	private static int nameCounter = 0;

	/*
	* JDK 1.1 serialVersionUID
	*/
	private static final long serialVersionUID = -2728009084054400034L;

	/**
	* Creates a new panel using the default layout manager.
	* The default layout manager for all panels is the
	* <code>FlowLayout</code> class.
	*/
	public Panel() {
	this(new FlowLayout());
	}

	/**
	* Creates a new panel with the specified layout manager.
	* @param layout the layout manager for this panel.
	* @since JDK1.1
	*/
	public Panel(LayoutManager layout) {
	setLayout(layout);
	}

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

	/**
	* Creates the Panel's peer. The peer allows you to modify the
	* appearance of the panel without changing its functionality.
	*/

	public void addNotify() {
	synchronized (getTreeLock()) {
	if (peer == null)
	peer = getToolkit().createPanel(this);
	super.addNotify();
	}
	}

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

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

	/**
	* This class implements accessibility support for the
	* <code>Panel</code> class. It provides an implementation of the
	* Java Accessibility API appropriate to panel user-interface elements.
	* @since 1.3
	*/
	protected class AccessibleAWTPanel extends AccessibleAWTContainer {

	private static final long serialVersionUID = -6409552226660031050L;

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

	}

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