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	/*
	* Copyright (c) 1996, 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 java.awt.event;

	import java.awt.AWTEvent;
	import java.awt.Component;
	import java.awt.Rectangle;
	import java.lang.annotation.Native;

	/**
	* A low-level event which indicates that a component moved, changed
	* size, or changed visibility (also, the root class for the other
	* component-level events).
	* <P>
	* Component events are provided for notification purposes ONLY;
	* The AWT will automatically handle component moves and resizes
	* internally so that GUI layout works properly regardless of
	* whether a program is receiving these events or not.
	* <P>
	* In addition to serving as the base class for other component-related
	* events (InputEvent, FocusEvent, WindowEvent, ContainerEvent),
	* this class defines the events that indicate changes in
	* a component's size, position, or visibility.
	* <P>
	* This low-level event is generated by a component object (such as a
	* List) when the component is moved, resized, rendered invisible, or made
	* visible again. The event is passed to every <code>ComponentListener</code>
	* or <code>ComponentAdapter</code> object which registered to receive such
	* events using the component's <code>addComponentListener</code> method.
	* (<code>ComponentAdapter</code> objects implement the
	* <code>ComponentListener</code> interface.) Each such listener object
	* gets this <code>ComponentEvent</code> when the event occurs.
	* <p>
	* An unspecified behavior will be caused if the {@code id} parameter
	* of any particular {@code ComponentEvent} instance is not
	* in the range from {@code COMPONENT_FIRST} to {@code COMPONENT_LAST}.
	*
	* @see ComponentAdapter
	* @see ComponentListener
	* @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/componentlistener.html">Tutorial: Writing a Component Listener</a>
	*
	* @author Carl Quinn
	* @since 1.1
	*/
	public class ComponentEvent extends AWTEvent {

	/**
	* The first number in the range of ids used for component events.
	*/
	public static final int COMPONENT_FIRST = 100;

	/**
	* The last number in the range of ids used for component events.
	*/
	public static final int COMPONENT_LAST = 103;

	/**
	* This event indicates that the component's position changed.
	*/
	@Native public static final int COMPONENT_MOVED = COMPONENT_FIRST;

	/**
	* This event indicates that the component's size changed.
	*/
	@Native public static final int COMPONENT_RESIZED = 1 + COMPONENT_FIRST;

	/**
	* This event indicates that the component was made visible.
	*/
	@Native public static final int COMPONENT_SHOWN = 2 + COMPONENT_FIRST;

	/**
	* This event indicates that the component was rendered invisible.
	*/
	@Native public static final int COMPONENT_HIDDEN = 3 + COMPONENT_FIRST;

	/*
	* JDK 1.1 serialVersionUID
	*/
	private static final long serialVersionUID = 8101406823902992965L;

	/**
	* Constructs a <code>ComponentEvent</code> object.
	* <p> This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	*
	* @param source The <code>Component</code> that originated the event
	* @param id An integer indicating the type of event.
	* For information on allowable values, see
	* the class description for {@link ComponentEvent}
	* @throws IllegalArgumentException if <code>source</code> is null
	* @see #getComponent()
	* @see #getID()
	*/
	public ComponentEvent(Component source, int id) {
	super(source, id);
	}

	/**
	* Returns the originator of the event.
	*
	* @return the <code>Component</code> object that originated
	* the event, or <code>null</code> if the object is not a
	* <code>Component</code>.
	*/
	public Component getComponent() {
	return (source instanceof Component) ? (Component)source : null;
	}

	/**
	* Returns a parameter string identifying this event.
	* This method is useful for event-logging and for debugging.
	*
	* @return a string identifying the event and its attributes
	*/
	public String paramString() {
	String typeStr;
	Rectangle b = (source !=null
	? ((Component)source).getBounds()
	: null);

	switch(id) {
	case COMPONENT_SHOWN:
	typeStr = "COMPONENT_SHOWN";
	break;
	case COMPONENT_HIDDEN:
	typeStr = "COMPONENT_HIDDEN";
	break;
	case COMPONENT_MOVED:
	typeStr = "COMPONENT_MOVED ("+
	b.x+","+b.y+" "+b.width+"x"+b.height+")";
	break;
	case COMPONENT_RESIZED:
	typeStr = "COMPONENT_RESIZED ("+
	b.x+","+b.y+" "+b.width+"x"+b.height+")";
	break;
	default:
	typeStr = "unknown type";
	}
	return typeStr;
	}
	}

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