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	/*
	* Copyright (c) 1997, 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 javax.swing;

	import java.awt.AWTKeyStroke;
	import java.awt.event.KeyEvent;

	/**
	* A KeyStroke represents a key action on the keyboard, or equivalent input
	* device. KeyStrokes can correspond to only a press or release of a particular
	* key, just as KEY_PRESSED and KEY_RELEASED KeyEvents do; alternately, they
	* can correspond to typing a specific Java character, just as KEY_TYPED
	* KeyEvents do. In all cases, KeyStrokes can specify modifiers (alt, shift,
	* control, meta, altGraph, or a combination thereof) which must be present during the
	* action for an exact match.
	* <p>
	* KeyStrokes are used to define high-level (semantic) action events. Instead
	* of trapping every keystroke and throwing away the ones you are not
	* interested in, those keystrokes you care about automatically initiate
	* actions on the Components with which they are registered.
	* <p>
	* KeyStrokes are immutable, and are intended to be unique. Client code cannot
	* create a KeyStroke; a variant of <code>getKeyStroke</code> must be used
	* instead. These factory methods allow the KeyStroke implementation to cache
	* and share instances efficiently.
	* <p>
	* <strong>Warning:</strong>
	* Serialized objects of this class will not be compatible with
	* future Swing releases. The current serialization support is
	* appropriate for short term storage or RMI between applications running
	* the same version of Swing. As of 1.4, support for long term storage
	* of all JavaBeans™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*
	* @see javax.swing.text.Keymap
	* @see #getKeyStroke
	*
	* @author Arnaud Weber
	* @author David Mendenhall
	*/
	public class KeyStroke extends AWTKeyStroke {

	/**
	* Serial Version ID.
	*/
	private static final long serialVersionUID = -9060180771037902530L;

	private KeyStroke() {
	}
	private KeyStroke(char keyChar, int keyCode, int modifiers,
	boolean onKeyRelease) {
	super(keyChar, keyCode, modifiers, onKeyRelease);
	}

	/**
	* Returns a shared instance of a <code>KeyStroke</code>
	* that represents a <code>KEY_TYPED</code> event for the
	* specified character.
	*
	* @param keyChar the character value for a keyboard key
	* @return a KeyStroke object for that key
	*/
	public static KeyStroke getKeyStroke(char keyChar) {
	synchronized (AWTKeyStroke.class) {
	registerSubclass(KeyStroke.class);
	return (KeyStroke)getAWTKeyStroke(keyChar);
	}
	}

	/**
	* Returns an instance of a KeyStroke, specifying whether the key is
	* considered to be activated when it is pressed or released. Unlike all
	* other factory methods in this class, the instances returned by this
	* method are not necessarily cached or shared.
	*
	* @param keyChar the character value for a keyboard key
	* @param onKeyRelease <code>true</code> if this KeyStroke corresponds to a
	* key release; <code>false</code> otherwise.
	* @return a KeyStroke object for that key
	* @deprecated use getKeyStroke(char)
	*/
	@Deprecated
	public static KeyStroke getKeyStroke(char keyChar, boolean onKeyRelease) {
	return new KeyStroke(keyChar, KeyEvent.VK_UNDEFINED, 0, onKeyRelease);
	}

	/**
	* Returns a shared instance of a {@code KeyStroke}
	* that represents a {@code KEY_TYPED} event for the
	* specified Character object and a
	* set of modifiers. Note that the first parameter is of type Character
	* rather than char. This is to avoid inadvertent clashes with calls to
	* <code>getKeyStroke(int keyCode, int modifiers)</code>.
	*
	* The modifiers consist of any combination of following:<ul>
	* <li>java.awt.event.InputEvent.SHIFT_DOWN_MASK
	* <li>java.awt.event.InputEvent.CTRL_DOWN_MASK
	* <li>java.awt.event.InputEvent.META_DOWN_MASK
	* <li>java.awt.event.InputEvent.ALT_DOWN_MASK
	* <li>java.awt.event.InputEvent.ALT_GRAPH_DOWN_MASK
	* </ul>
	* The old modifiers listed below also can be used, but they are
	* mapped to _DOWN_ modifiers. <ul>
	* <li>java.awt.event.InputEvent.SHIFT_MASK
	* <li>java.awt.event.InputEvent.CTRL_MASK
	* <li>java.awt.event.InputEvent.META_MASK
	* <li>java.awt.event.InputEvent.ALT_MASK
	* <li>java.awt.event.InputEvent.ALT_GRAPH_MASK
	* </ul>
	* also can be used, but they are mapped to _DOWN_ modifiers.
	*
	* Since these numbers are all different powers of two, any combination of
	* them is an integer in which each bit represents a different modifier
	* key. Use 0 to specify no modifiers.
	*
	* @param keyChar the Character object for a keyboard character
	* @param modifiers a bitwise-ored combination of any modifiers
	* @return an KeyStroke object for that key
	* @throws IllegalArgumentException if keyChar is null
	*
	* @see java.awt.event.InputEvent
	* @since 1.3
	*/
	public static KeyStroke getKeyStroke(Character keyChar, int modifiers) {
	synchronized (AWTKeyStroke.class) {
	registerSubclass(KeyStroke.class);
	return (KeyStroke)getAWTKeyStroke(keyChar, modifiers);
	}
	}

	/**
	* Returns a shared instance of a KeyStroke, given a numeric key code and a
	* set of modifiers, specifying whether the key is activated when it is
	* pressed or released.
	* <p>
	* The "virtual key" constants defined in java.awt.event.KeyEvent can be
	* used to specify the key code. For example:<ul>
	* <li>java.awt.event.KeyEvent.VK_ENTER
	* <li>java.awt.event.KeyEvent.VK_TAB
	* <li>java.awt.event.KeyEvent.VK_SPACE
	* </ul>
	* Alternatively, the key code may be obtained by calling
	* <code>java.awt.event.KeyEvent.getExtendedKeyCodeForChar</code>.
	*
	* The modifiers consist of any combination of:<ul>
	* <li>java.awt.event.InputEvent.SHIFT_DOWN_MASK
	* <li>java.awt.event.InputEvent.CTRL_DOWN_MASK
	* <li>java.awt.event.InputEvent.META_DOWN_MASK
	* <li>java.awt.event.InputEvent.ALT_DOWN_MASK
	* <li>java.awt.event.InputEvent.ALT_GRAPH_DOWN_MASK
	* </ul>
	* The old modifiers <ul>
	* <li>java.awt.event.InputEvent.SHIFT_MASK
	* <li>java.awt.event.InputEvent.CTRL_MASK
	* <li>java.awt.event.InputEvent.META_MASK
	* <li>java.awt.event.InputEvent.ALT_MASK
	* <li>java.awt.event.InputEvent.ALT_GRAPH_MASK
	* </ul>
	* also can be used, but they are mapped to _DOWN_ modifiers.
	*
	* Since these numbers are all different powers of two, any combination of
	* them is an integer in which each bit represents a different modifier
	* key. Use 0 to specify no modifiers.
	*
	* @param keyCode an int specifying the numeric code for a keyboard key
	* @param modifiers a bitwise-ored combination of any modifiers
	* @param onKeyRelease <code>true</code> if the KeyStroke should represent
	* a key release; <code>false</code> otherwise.
	* @return a KeyStroke object for that key
	*
	* @see java.awt.event.KeyEvent
	* @see java.awt.event.InputEvent
	*/
	public static KeyStroke getKeyStroke(int keyCode, int modifiers,
	boolean onKeyRelease) {
	synchronized (AWTKeyStroke.class) {
	registerSubclass(KeyStroke.class);
	return (KeyStroke)getAWTKeyStroke(keyCode, modifiers,
	onKeyRelease);
	}
	}

	/**
	* Returns a shared instance of a KeyStroke, given a numeric key code and a
	* set of modifiers. The returned KeyStroke will correspond to a key press.
	* <p>
	* The "virtual key" constants defined in java.awt.event.KeyEvent can be
	* used to specify the key code. For example:<ul>
	* <li>java.awt.event.KeyEvent.VK_ENTER
	* <li>java.awt.event.KeyEvent.VK_TAB
	* <li>java.awt.event.KeyEvent.VK_SPACE
	* </ul>
	* Alternatively, the key code may be obtained by calling
	* <code>java.awt.event.KeyEvent.getExtendedKeyCodeForChar</code>.
	*
	* The modifiers consist of any combination of:<ul>
	* <li>java.awt.event.InputEvent.SHIFT_DOWN_MASK
	* <li>java.awt.event.InputEvent.CTRL_DOWN_MASK
	* <li>java.awt.event.InputEvent.META_DOWN_MASK
	* <li>java.awt.event.InputEvent.ALT_DOWN_MASK
	* <li>java.awt.event.InputEvent.ALT_GRAPH_DOWN_MASK
	* </ul>
	* The old modifiers <ul>
	* <li>java.awt.event.InputEvent.SHIFT_MASK
	* <li>java.awt.event.InputEvent.CTRL_MASK
	* <li>java.awt.event.InputEvent.META_MASK
	* <li>java.awt.event.InputEvent.ALT_MASK
	* <li>java.awt.event.InputEvent.ALT_GRAPH_MASK
	* </ul>
	* also can be used, but they are mapped to _DOWN_ modifiers.
	*
	* Since these numbers are all different powers of two, any combination of
	* them is an integer in which each bit represents a different modifier
	* key. Use 0 to specify no modifiers.
	*
	* @param keyCode an int specifying the numeric code for a keyboard key
	* @param modifiers a bitwise-ored combination of any modifiers
	* @return a KeyStroke object for that key
	*
	* @see java.awt.event.KeyEvent
	* @see java.awt.event.InputEvent
	*/
	public static KeyStroke getKeyStroke(int keyCode, int modifiers) {
	synchronized (AWTKeyStroke.class) {
	registerSubclass(KeyStroke.class);
	return (KeyStroke)getAWTKeyStroke(keyCode, modifiers);
	}
	}

	/**
	* Returns a KeyStroke which represents the stroke which generated a given
	* KeyEvent.
	* <p>
	* This method obtains the keyChar from a KeyTyped event, and the keyCode
	* from a KeyPressed or KeyReleased event. The KeyEvent modifiers are
	* obtained for all three types of KeyEvent.
	*
	* @param anEvent the KeyEvent from which to obtain the KeyStroke
	* @throws NullPointerException if <code>anEvent</code> is null
	* @return the KeyStroke that precipitated the event
	*/
	public static KeyStroke getKeyStrokeForEvent(KeyEvent anEvent) {
	synchronized (AWTKeyStroke.class) {
	registerSubclass(KeyStroke.class);
	return (KeyStroke)getAWTKeyStrokeForEvent(anEvent);
	}
	}

	/**
	* Parses a string and returns a <code>KeyStroke</code>.
	* The string must have the following syntax:
	* <pre>
	* <modifiers>* (<typedID> \| <pressedReleasedID>)
	*
	* modifiers := shift \| control \| ctrl \| meta \| alt \| altGraph
	* typedID := typed <typedKey>
	* typedKey := string of length 1 giving Unicode character.
	* pressedReleasedID := (pressed \| released) key
	* key := KeyEvent key code name, i.e. the name following "VK_".
	* </pre>
	* If typed, pressed or released is not specified, pressed is assumed. Here
	* are some examples:
	* <pre>
	* "INSERT" => getKeyStroke(KeyEvent.VK_INSERT, 0);
	* "control DELETE" => getKeyStroke(KeyEvent.VK_DELETE, InputEvent.CTRL_MASK);
	* "alt shift X" => getKeyStroke(KeyEvent.VK_X, InputEvent.ALT_MASK \| InputEvent.SHIFT_MASK);
	* "alt shift released X" => getKeyStroke(KeyEvent.VK_X, InputEvent.ALT_MASK \| InputEvent.SHIFT_MASK, true);
	* "typed a" => getKeyStroke('a');
	* </pre>
	*
	* In order to maintain backward-compatibility, specifying a null String,
	* or a String which is formatted incorrectly, returns null.
	*
	* @param s a String formatted as described above
	* @return a KeyStroke object for that String, or null if the specified
	* String is null, or is formatted incorrectly
	*
	* @see java.awt.event.KeyEvent
	*/
	public static KeyStroke getKeyStroke(String s) {
	if (s == null \|\| s.length() == 0) {
	return null;
	}
	synchronized (AWTKeyStroke.class) {
	registerSubclass(KeyStroke.class);
	try {
	return (KeyStroke)getAWTKeyStroke(s);
	} catch (IllegalArgumentException e) {
	return null;
	}
	}
	}
	}

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