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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.Event;
	import java.lang.annotation.Native;

	/**
	* A semantic event which indicates that a component-defined action occurred.
	* This high-level event is generated by a component (such as a
	* <code>Button</code>) when
	* the component-specific action occurs (such as being pressed).
	* The event is passed to every <code>ActionListener</code> object
	* that registered to receive such events using the component's
	* <code>addActionListener</code> method.
	* <p>
	* <b>Note:</b> To invoke an <code>ActionEvent</code> on a
	* <code>Button</code> using the keyboard, use the Space bar.
	* <P>
	* The object that implements the <code>ActionListener</code> interface
	* gets this <code>ActionEvent</code> when the event occurs. The listener
	* is therefore spared the details of processing individual mouse movements
	* and mouse clicks, and can instead process a "meaningful" (semantic)
	* event like "button pressed".
	* <p>
	* An unspecified behavior will be caused if the {@code id} parameter
	* of any particular {@code ActionEvent} instance is not
	* in the range from {@code ACTION_FIRST} to {@code ACTION_LAST}.
	*
	* @see ActionListener
	* @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html">Tutorial: How to Write an Action Listener</a>
	*
	* @author Carl Quinn
	* @since 1.1
	*/
	public class ActionEvent extends AWTEvent {

	/**
	* The shift modifier. An indicator that the shift key was held
	* down during the event.
	*/
	public static final int SHIFT_MASK = Event.SHIFT_MASK;

	/**
	* The control modifier. An indicator that the control key was held
	* down during the event.
	*/
	public static final int CTRL_MASK = Event.CTRL_MASK;

	/**
	* The meta modifier. An indicator that the meta key was held
	* down during the event.
	*/
	public static final int META_MASK = Event.META_MASK;

	/**
	* The alt modifier. An indicator that the alt key was held
	* down during the event.
	*/
	public static final int ALT_MASK = Event.ALT_MASK;


	/**
	* The first number in the range of ids used for action events.
	*/
	public static final int ACTION_FIRST = 1001;

	/**
	* The last number in the range of ids used for action events.
	*/
	public static final int ACTION_LAST = 1001;

	/**
	* This event id indicates that a meaningful action occurred.
	*/
	@Native public static final int ACTION_PERFORMED = ACTION_FIRST; //Event.ACTION_EVENT

	/**
	* The nonlocalized string that gives more details
	* of what actually caused the event.
	* This information is very specific to the component
	* that fired it.

	* @serial
	* @see #getActionCommand
	*/
	String actionCommand;

	/**
	* Timestamp of when this event occurred. Because an ActionEvent is a high-
	* level, semantic event, the timestamp is typically the same as an
	* underlying InputEvent.
	*
	* @serial
	* @see #getWhen
	*/
	long when;

	/**
	* This represents the key modifier that was selected,
	* and is used to determine the state of the selected key.
	* If no modifier has been selected it will default to
	* zero.
	*
	* @serial
	* @see #getModifiers
	*/
	int modifiers;

	/*
	* JDK 1.1 serialVersionUID
	*/
	private static final long serialVersionUID = -7671078796273832149L;

	/**
	* Constructs an <code>ActionEvent</code> object.
	* <p>
	* This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	* A <code>null</code> <code>command</code> string is legal,
	* but not recommended.
	*
	* @param source The object that originated the event
	* @param id An integer that identifies the event.
	* For information on allowable values, see
	* the class description for {@link ActionEvent}
	* @param command A string that may specify a command (possibly one
	* of several) associated with the event
	* @throws IllegalArgumentException if <code>source</code> is null
	* @see #getSource()
	* @see #getID()
	* @see #getActionCommand()
	*/
	public ActionEvent(Object source, int id, String command) {
	this(source, id, command, 0);
	}

	/**
	* Constructs an <code>ActionEvent</code> object with modifier keys.
	* <p>
	* This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	* A <code>null</code> <code>command</code> string is legal,
	* but not recommended.
	*
	* @param source The object that originated the event
	* @param id An integer that identifies the event.
	* For information on allowable values, see
	* the class description for {@link ActionEvent}
	* @param command A string that may specify a command (possibly one
	* of several) associated with the event
	* @param modifiers The modifier keys down during event
	* (shift, ctrl, alt, meta).
	* Passing negative parameter is not recommended.
	* Zero value means that no modifiers were passed
	* @throws IllegalArgumentException if <code>source</code> is null
	* @see #getSource()
	* @see #getID()
	* @see #getActionCommand()
	* @see #getModifiers()
	*/
	public ActionEvent(Object source, int id, String command, int modifiers) {
	this(source, id, command, 0, modifiers);
	}

	/**
	* Constructs an <code>ActionEvent</code> object with the specified
	* modifier keys and timestamp.
	* <p>
	* This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	* A <code>null</code> <code>command</code> string is legal,
	* but not recommended.
	*
	* @param source The object that originated the event
	* @param id An integer that identifies the event.
	* For information on allowable values, see
	* the class description for {@link ActionEvent}
	* @param command A string that may specify a command (possibly one
	* of several) associated with the event
	* @param modifiers The modifier keys down during event
	* (shift, ctrl, alt, meta).
	* Passing negative parameter is not recommended.
	* Zero value means that no modifiers were passed
	* @param when A long that gives the time the event occurred.
	* Passing negative or zero value
	* is not recommended
	* @throws IllegalArgumentException if <code>source</code> is null
	* @see #getSource()
	* @see #getID()
	* @see #getActionCommand()
	* @see #getModifiers()
	* @see #getWhen()
	*
	* @since 1.4
	*/
	public ActionEvent(Object source, int id, String command, long when,
	int modifiers) {
	super(source, id);
	this.actionCommand = command;
	this.when = when;
	this.modifiers = modifiers;
	}

	/**
	* Returns the command string associated with this action.
	* This string allows a "modal" component to specify one of several
	* commands, depending on its state. For example, a single button might
	* toggle between "show details" and "hide details". The source object
	* and the event would be the same in each case, but the command string
	* would identify the intended action.
	* <p>
	* Note that if a <code>null</code> command string was passed
	* to the constructor for this <code>ActionEvent</code>, this
	* this method returns <code>null</code>.
	*
	* @return the string identifying the command for this event
	*/
	public String getActionCommand() {
	return actionCommand;
	}

	/**
	* Returns the timestamp of when this event occurred. Because an
	* ActionEvent is a high-level, semantic event, the timestamp is typically
	* the same as an underlying InputEvent.
	*
	* @return this event's timestamp
	* @since 1.4
	*/
	public long getWhen() {
	return when;
	}

	/**
	* Returns the modifier keys held down during this action event.
	*
	* @return the bitwise-or of the modifier constants
	*/
	public int getModifiers() {
	return modifiers;
	}

	/**
	* Returns a parameter string identifying this action event.
	* This method is useful for event-logging and for debugging.
	*
	* @return a string identifying the event and its associated command
	*/
	public String paramString() {
	String typeStr;
	switch(id) {
	case ACTION_PERFORMED:
	typeStr = "ACTION_PERFORMED";
	break;
	default:
	typeStr = "unknown type";
	}
	return typeStr + ",cmd="+actionCommand+",when="+when+",modifiers="+
	KeyEvent.getKeyModifiersText(modifiers);
	}
	}

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