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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.ItemSelectable;

	/**
	* A semantic event which indicates that an item was selected or deselected.
	* This high-level event is generated by an ItemSelectable object (such as a
	* List) when an item is selected or deselected by the user.
	* The event is passed to every <code>ItemListener</code> object which
	* registered to receive such events using the component's
	* <code>addItemListener</code> method.
	* <P>
	* The object that implements the <code>ItemListener</code> interface gets
	* this <code>ItemEvent</code> when the event occurs. The listener is
	* spared the details of processing individual mouse movements and mouse
	* clicks, and can instead process a "meaningful" (semantic) event like
	* "item selected" or "item deselected".
	* <p>
	* An unspecified behavior will be caused if the {@code id} parameter
	* of any particular {@code ItemEvent} instance is not
	* in the range from {@code ITEM_FIRST} to {@code ITEM_LAST}.
	* <p>
	* The {@code stateChange} of any {@code ItemEvent} instance takes one of the following
	* values:
	* <ul>
	* <li> {@code ItemEvent.SELECTED}
	* <li> {@code ItemEvent.DESELECTED}
	* </ul>
	* Assigning the value different from listed above will cause an unspecified behavior.
	*
	* @author Carl Quinn
	*
	* @see java.awt.ItemSelectable
	* @see ItemListener
	* @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/itemlistener.html">Tutorial: Writing an Item Listener</a>
	*
	* @since 1.1
	*/
	public class ItemEvent extends AWTEvent {

	/**
	* The first number in the range of ids used for item events.
	*/
	public static final int ITEM_FIRST = 701;

	/**
	* The last number in the range of ids used for item events.
	*/
	public static final int ITEM_LAST = 701;

	/**
	* This event id indicates that an item's state changed.
	*/
	public static final int ITEM_STATE_CHANGED = ITEM_FIRST; //Event.LIST_SELECT

	/**
	* This state-change value indicates that an item was selected.
	*/
	public static final int SELECTED = 1;

	/**
	* This state-change-value indicates that a selected item was deselected.
	*/
	public static final int DESELECTED = 2;

	/**
	* The item whose selection state has changed.
	*
	* @serial
	* @see #getItem()
	*/
	Object item;

	/**
	* <code>stateChange</code> indicates whether the <code>item</code>
	* was selected or deselected.
	*
	* @serial
	* @see #getStateChange()
	*/
	int stateChange;

	/*
	* JDK 1.1 serialVersionUID
	*/
	private static final long serialVersionUID = -608708132447206933L;

	/**
	* Constructs an <code>ItemEvent</code> object.
	* <p> This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	*
	* @param source The <code>ItemSelectable</code> object
	* that originated the event
	* @param id The integer that identifies the event type.
	* For information on allowable values, see
	* the class description for {@link ItemEvent}
	* @param item An object -- the item affected by the event
	* @param stateChange An integer that indicates whether the item was
	* selected or deselected.
	* For information on allowable values, see
	* the class description for {@link ItemEvent}
	* @throws IllegalArgumentException if <code>source</code> is null
	* @see #getItemSelectable()
	* @see #getID()
	* @see #getStateChange()
	*/
	public ItemEvent(ItemSelectable source, int id, Object item, int stateChange) {
	super(source, id);
	this.item = item;
	this.stateChange = stateChange;
	}

	/**
	* Returns the originator of the event.
	*
	* @return the ItemSelectable object that originated the event.
	*/
	public ItemSelectable getItemSelectable() {
	return (ItemSelectable)source;
	}

	/**
	* Returns the item affected by the event.
	*
	* @return the item (object) that was affected by the event
	*/
	public Object getItem() {
	return item;
	}

	/**
	* Returns the type of state change (selected or deselected).
	*
	* @return an integer that indicates whether the item was selected
	* or deselected
	*
	* @see #SELECTED
	* @see #DESELECTED
	*/
	public int getStateChange() {
	return stateChange;
	}

	/**
	* Returns a parameter string identifying this item 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;
	switch(id) {
	case ITEM_STATE_CHANGED:
	typeStr = "ITEM_STATE_CHANGED";
	break;
	default:
	typeStr = "unknown type";
	}

	String stateStr;
	switch(stateChange) {
	case SELECTED:
	stateStr = "SELECTED";
	break;
	case DESELECTED:
	stateStr = "DESELECTED";
	break;
	default:
	stateStr = "unknown type";
	}
	return typeStr + ",item="+item + ",stateChange="+stateStr;
	}

	}

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