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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.Event;
	import java.awt.Component;
	import java.awt.GraphicsEnvironment;
	import java.awt.Toolkit;
	import java.util.Arrays;

	import sun.awt.AWTAccessor;
	import sun.util.logging.PlatformLogger;
	import sun.security.util.SecurityConstants;

	/**
	* The root event class for all component-level input events.
	*
	* Input events are delivered to listeners before they are
	* processed normally by the source where they originated.
	* This allows listeners and component subclasses to "consume"
	* the event so that the source will not process them in their
	* default manner. For example, consuming mousePressed events
	* on a Button component will prevent the Button from being
	* activated.
	*
	* @author Carl Quinn
	*
	* @see KeyEvent
	* @see KeyAdapter
	* @see MouseEvent
	* @see MouseAdapter
	* @see MouseMotionAdapter
	*
	* @since 1.1
	*/
	public abstract class InputEvent extends ComponentEvent {

	private static final PlatformLogger logger = PlatformLogger.getLogger("java.awt.event.InputEvent");

	/**
	* The Shift key modifier constant.
	* It is recommended that SHIFT_DOWN_MASK be used instead.
	*/
	public static final int SHIFT_MASK = Event.SHIFT_MASK;

	/**
	* The Control key modifier constant.
	* It is recommended that CTRL_DOWN_MASK be used instead.
	*/
	public static final int CTRL_MASK = Event.CTRL_MASK;

	/**
	* The Meta key modifier constant.
	* It is recommended that META_DOWN_MASK be used instead.
	*/
	public static final int META_MASK = Event.META_MASK;

	/**
	* The Alt key modifier constant.
	* It is recommended that ALT_DOWN_MASK be used instead.
	*/
	public static final int ALT_MASK = Event.ALT_MASK;

	/**
	* The AltGraph key modifier constant.
	*/
	public static final int ALT_GRAPH_MASK = 1 << 5;

	/**
	* The Mouse Button1 modifier constant.
	* It is recommended that BUTTON1_DOWN_MASK be used instead.
	*/
	public static final int BUTTON1_MASK = 1 << 4;

	/**
	* The Mouse Button2 modifier constant.
	* It is recommended that BUTTON2_DOWN_MASK be used instead.
	* Note that BUTTON2_MASK has the same value as ALT_MASK.
	*/
	public static final int BUTTON2_MASK = Event.ALT_MASK;

	/**
	* The Mouse Button3 modifier constant.
	* It is recommended that BUTTON3_DOWN_MASK be used instead.
	* Note that BUTTON3_MASK has the same value as META_MASK.
	*/
	public static final int BUTTON3_MASK = Event.META_MASK;

	/**
	* The Shift key extended modifier constant.
	* @since 1.4
	*/
	public static final int SHIFT_DOWN_MASK = 1 << 6;

	/**
	* The Control key extended modifier constant.
	* @since 1.4
	*/
	public static final int CTRL_DOWN_MASK = 1 << 7;

	/**
	* The Meta key extended modifier constant.
	* @since 1.4
	*/
	public static final int META_DOWN_MASK = 1 << 8;

	/**
	* The Alt key extended modifier constant.
	* @since 1.4
	*/
	public static final int ALT_DOWN_MASK = 1 << 9;

	/**
	* The Mouse Button1 extended modifier constant.
	* @since 1.4
	*/
	public static final int BUTTON1_DOWN_MASK = 1 << 10;

	/**
	* The Mouse Button2 extended modifier constant.
	* @since 1.4
	*/
	public static final int BUTTON2_DOWN_MASK = 1 << 11;

	/**
	* The Mouse Button3 extended modifier constant.
	* @since 1.4
	*/
	public static final int BUTTON3_DOWN_MASK = 1 << 12;

	/**
	* The AltGraph key extended modifier constant.
	* @since 1.4
	*/
	public static final int ALT_GRAPH_DOWN_MASK = 1 << 13;

	/**
	* An array of extended modifiers for additional buttons.
	* @see getButtonDownMasks
	* There are twenty buttons fit into 4byte space.
	* one more bit is reserved for FIRST_HIGH_BIT.
	* @since 7.0
	*/
	private static final int [] BUTTON_DOWN_MASK = new int [] { BUTTON1_DOWN_MASK,
	BUTTON2_DOWN_MASK,
	BUTTON3_DOWN_MASK,
	1<<14, //4th phisical button (this is not a wheel!)
	1<<15, //(this is not a wheel!)
	1<<16,
	1<<17,
	1<<18,
	1<<19,
	1<<20,
	1<<21,
	1<<22,
	1<<23,
	1<<24,
	1<<25,
	1<<26,
	1<<27,
	1<<28,
	1<<29,
	1<<30};

	/**
	* A method to access an array of extended modifiers for additional buttons.
	* @since 7.0
	*/
	private static int [] getButtonDownMasks(){
	return Arrays.copyOf(BUTTON_DOWN_MASK, BUTTON_DOWN_MASK.length);
	}


	/**
	* A method to obtain a mask for any existing mouse button.
	* The returned mask may be used for different purposes. Following are some of them:
	* <ul>
	* <li> {@link java.awt.Robot#mousePress(int) mousePress(buttons)} and
	* {@link java.awt.Robot#mouseRelease(int) mouseRelease(buttons)}
	* <li> as a {@code modifiers} parameter when creating a new {@link MouseEvent} instance
	* <li> to check {@link MouseEvent#getModifiersEx() modifiersEx} of existing {@code MouseEvent}
	* </ul>
	* @param button is a number to represent a button starting from 1.
	* For example,
	* <pre>
	* int button = InputEvent.getMaskForButton(1);
	* </pre>
	* will have the same meaning as
	* <pre>
	* int button = InputEvent.getMaskForButton(MouseEvent.BUTTON1);
	* </pre>
	* because {@link MouseEvent#BUTTON1 MouseEvent.BUTTON1} equals to 1.
	* If a mouse has three enabled buttons(see {@link java.awt.MouseInfo#getNumberOfButtons() MouseInfo.getNumberOfButtons()})
	* then the values from the left column passed into the method will return
	* corresponding values from the right column:
	* <PRE>
	* <b>button </b> <b>returned mask</b>
	* {@link MouseEvent#BUTTON1 BUTTON1} {@link MouseEvent#BUTTON1_DOWN_MASK BUTTON1_DOWN_MASK}
	* {@link MouseEvent#BUTTON2 BUTTON2} {@link MouseEvent#BUTTON2_DOWN_MASK BUTTON2_DOWN_MASK}
	* {@link MouseEvent#BUTTON3 BUTTON3} {@link MouseEvent#BUTTON3_DOWN_MASK BUTTON3_DOWN_MASK}
	* </PRE>
	* If a mouse has more than three enabled buttons then more values
	* are admissible (4, 5, etc.). There is no assigned constants for these extended buttons.
	* The button masks for the extra buttons returned by this method have no assigned names like the
	* first three button masks.
	* <p>
	* This method has the following implementation restriction.
	* It returns masks for a limited number of buttons only. The maximum number is
	* implementation dependent and may vary.
	* This limit is defined by the relevant number
	* of buttons that may hypothetically exist on the mouse but it is greater than the
	* {@link java.awt.MouseInfo#getNumberOfButtons() MouseInfo.getNumberOfButtons()}.
	* <p>
	* @throws IllegalArgumentException if {@code button} is less than zero or greater than the number
	* of button masks reserved for buttons
	* @since 7.0
	* @see java.awt.MouseInfo#getNumberOfButtons()
	* @see Toolkit#areExtraMouseButtonsEnabled()
	* @see MouseEvent#getModifiers()
	* @see MouseEvent#getModifiersEx()
	*/
	public static int getMaskForButton(int button) {
	if (button <= 0 \|\| button > BUTTON_DOWN_MASK.length) {
	throw new IllegalArgumentException("button doesn\'t exist " + button);
	}
	return BUTTON_DOWN_MASK[button - 1];
	}

	// the constant below MUST be updated if any extra modifier
	// bits are to be added!
	// in fact, it is undesirable to add modifier bits
	// to the same field as this may break applications
	// see bug# 5066958
	static final int FIRST_HIGH_BIT = 1 << 31;

	static final int JDK_1_3_MODIFIERS = SHIFT_DOWN_MASK - 1;
	static final int HIGH_MODIFIERS = ~( FIRST_HIGH_BIT - 1 );

	/**
	* The input event's Time stamp in UTC format. The time stamp
	* indicates when the input event was created.
	*
	* @serial
	* @see #getWhen()
	*/
	long when;

	/**
	* The state of the modifier mask at the time the input
	* event was fired.
	*
	* @serial
	* @see #getModifiers()
	* @see #getModifiersEx()
	* @see java.awt.event.KeyEvent
	* @see java.awt.event.MouseEvent
	*/
	int modifiers;

	/*
	* A flag that indicates that this instance can be used to access
	* the system clipboard.
	*/
	private transient boolean canAccessSystemClipboard;

	static {
	/* ensure that the necessary native libraries are loaded */
	NativeLibLoader.loadLibraries();
	if (!GraphicsEnvironment.isHeadless()) {
	initIDs();
	}
	AWTAccessor.setInputEventAccessor(
	new AWTAccessor.InputEventAccessor() {
	public int[] getButtonDownMasks() {
	return InputEvent.getButtonDownMasks();
	}
	});
	}

	/**
	* Initialize JNI field and method IDs for fields that may be
	accessed from C.
	*/
	private static native void initIDs();

	/**
	* Constructs an InputEvent object with the specified source component,
	* modifiers, and type.
	* <p> This method throws an
	* <code>IllegalArgumentException</code> if <code>source</code>
	* is <code>null</code>.
	*
	* @param source the object where the event originated
	* @param id the integer that identifies the event type.
	* It is allowed to pass as parameter any value that
	* allowed for some subclass of {@code InputEvent} class.
	* Passing in the value different from those values result
	* in unspecified behavior
	* @param when a long int that gives the time the event occurred.
	* Passing negative or zero value
	* is not recommended
	* @param modifiers a modifier mask describing the modifier keys and mouse
	* buttons (for example, shift, ctrl, alt, and meta) that
	* are down during the event.
	* Only extended modifiers are allowed to be used as a
	* value for this parameter (see the {@link InputEvent#getModifiersEx}
	* class for the description of extended modifiers).
	* 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 #getWhen()
	* @see #getModifiers()
	*/
	InputEvent(Component source, int id, long when, int modifiers) {
	super(source, id);
	this.when = when;
	this.modifiers = modifiers;
	canAccessSystemClipboard = canAccessSystemClipboard();
	}

	private boolean canAccessSystemClipboard() {
	boolean b = false;

	if (!GraphicsEnvironment.isHeadless()) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null) {
	try {
	sm.checkPermission(SecurityConstants.AWT.ACCESS_CLIPBOARD_PERMISSION);
	b = true;
	} catch (SecurityException se) {
	if (logger.isLoggable(PlatformLogger.Level.FINE)) {
	logger.fine("InputEvent.canAccessSystemClipboard() got SecurityException ", se);
	}
	}
	} else {
	b = true;
	}
	}

	return b;
	}

	/**
	* Returns whether or not the Shift modifier is down on this event.
	*/
	public boolean isShiftDown() {
	return (modifiers & SHIFT_MASK) != 0;
	}

	/**
	* Returns whether or not the Control modifier is down on this event.
	*/
	public boolean isControlDown() {
	return (modifiers & CTRL_MASK) != 0;
	}

	/**
	* Returns whether or not the Meta modifier is down on this event.
	*/
	public boolean isMetaDown() {
	return (modifiers & META_MASK) != 0;
	}

	/**
	* Returns whether or not the Alt modifier is down on this event.
	*/
	public boolean isAltDown() {
	return (modifiers & ALT_MASK) != 0;
	}

	/**
	* Returns whether or not the AltGraph modifier is down on this event.
	*/
	public boolean isAltGraphDown() {
	return (modifiers & ALT_GRAPH_MASK) != 0;
	}

	/**
	* Returns the difference in milliseconds between the timestamp of when this event occurred and
	* midnight, January 1, 1970 UTC.
	*/
	public long getWhen() {
	return when;
	}

	/**
	* Returns the modifier mask for this event.
	*/
	public int getModifiers() {
	return modifiers & (JDK_1_3_MODIFIERS \| HIGH_MODIFIERS);
	}

	/**
	* Returns the extended modifier mask for this event.
	* <P>
	* Extended modifiers are the modifiers that ends with the _DOWN_MASK suffix,
	* such as ALT_DOWN_MASK, BUTTON1_DOWN_MASK, and others.
	* <P>
	* Extended modifiers represent the state of all modal keys,
	* such as ALT, CTRL, META, and the mouse buttons just after
	* the event occurred.
	* <P>
	* For example, if the user presses <b>button 1</b> followed by
	* <b>button 2</b>, and then releases them in the same order,
	* the following sequence of events is generated:
	* <PRE>
	* <code>MOUSE_PRESSED</code>: <code>BUTTON1_DOWN_MASK</code>
	* <code>MOUSE_PRESSED</code>: <code>BUTTON1_DOWN_MASK \| BUTTON2_DOWN_MASK</code>
	* <code>MOUSE_RELEASED</code>: <code>BUTTON2_DOWN_MASK</code>
	* <code>MOUSE_CLICKED</code>: <code>BUTTON2_DOWN_MASK</code>
	* <code>MOUSE_RELEASED</code>:
	* <code>MOUSE_CLICKED</code>:
	* </PRE>
	* <P>
	* It is not recommended to compare the return value of this method
	* using <code>==</code> because new modifiers can be added in the future.
	* For example, the appropriate way to check that SHIFT and BUTTON1 are
	* down, but CTRL is up is demonstrated by the following code:
	* <PRE>
	* int onmask = SHIFT_DOWN_MASK \| BUTTON1_DOWN_MASK;
	* int offmask = CTRL_DOWN_MASK;
	* if ((event.getModifiersEx() & (onmask \| offmask)) == onmask) {
	* ...
	* }
	* </PRE>
	* The above code will work even if new modifiers are added.
	*
	* @since 1.4
	*/
	public int getModifiersEx() {
	return modifiers & ~JDK_1_3_MODIFIERS;
	}

	/**
	* Consumes this event so that it will not be processed
	* in the default manner by the source which originated it.
	*/
	public void consume() {
	consumed = true;
	}

	/**
	* Returns whether or not this event has been consumed.
	* @see #consume
	*/
	public boolean isConsumed() {
	return consumed;
	}

	// state serialization compatibility with JDK 1.1
	static final long serialVersionUID = -2482525981698309786L;

	/**
	* Returns a String describing the extended modifier keys and
	* mouse buttons, such as "Shift", "Button1", or "Ctrl+Shift".
	* These strings can be localized by changing the
	* <code>awt.properties</code> file.
	* <p>
	* Note that passing negative parameter is incorrect,
	* and will cause the returning an unspecified string.
	* Zero parameter means that no modifiers were passed and will
	* cause the returning an empty string.
	*
	* @param modifiers a modifier mask describing the extended
	* modifier keys and mouse buttons for the event
	* @return a text description of the combination of extended
	* modifier keys and mouse buttons that were held down
	* during the event.
	* @since 1.4
	*/
	public static String getModifiersExText(int modifiers) {
	StringBuilder buf = new StringBuilder();
	if ((modifiers & InputEvent.META_DOWN_MASK) != 0) {
	buf.append(Toolkit.getProperty("AWT.meta", "Meta"));
	buf.append("+");
	}
	if ((modifiers & InputEvent.CTRL_DOWN_MASK) != 0) {
	buf.append(Toolkit.getProperty("AWT.control", "Ctrl"));
	buf.append("+");
	}
	if ((modifiers & InputEvent.ALT_DOWN_MASK) != 0) {
	buf.append(Toolkit.getProperty("AWT.alt", "Alt"));
	buf.append("+");
	}
	if ((modifiers & InputEvent.SHIFT_DOWN_MASK) != 0) {
	buf.append(Toolkit.getProperty("AWT.shift", "Shift"));
	buf.append("+");
	}
	if ((modifiers & InputEvent.ALT_GRAPH_DOWN_MASK) != 0) {
	buf.append(Toolkit.getProperty("AWT.altGraph", "Alt Graph"));
	buf.append("+");
	}

	int buttonNumber = 1;
	for (int mask : InputEvent.BUTTON_DOWN_MASK){
	if ((modifiers & mask) != 0) {
	buf.append(Toolkit.getProperty("AWT.button"+buttonNumber, "Button"+buttonNumber));
	buf.append("+");
	}
	buttonNumber++;
	}
	if (buf.length() > 0) {
	buf.setLength(buf.length()-1); // remove trailing '+'
	}
	return buf.toString();
	}
	}

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