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	/*
	* Copyright (c) 1998, 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.util.*;
	import java.awt.*;
	import java.awt.event.*;
	import java.applet.*;
	import java.beans.*;
	import javax.swing.event.*;
	import sun.awt.EmbeddedFrame;

	/**
	* The KeyboardManager class is used to help dispatch keyboard actions for the
	* WHEN_IN_FOCUSED_WINDOW style actions. Actions with other conditions are handled
	* directly in JComponent.
	*
	* Here's a description of the symantics of how keyboard dispatching should work
	* atleast as I understand it.
	*
	* KeyEvents are dispatched to the focused component. The focus manager gets first
	* crack at processing this event. If the focus manager doesn't want it, then
	* the JComponent calls super.processKeyEvent() this allows listeners a chance
	* to process the event.
	*
	* If none of the listeners "consumes" the event then the keybindings get a shot.
	* This is where things start to get interesting. First, KeyStokes defined with the
	* WHEN_FOCUSED condition get a chance. If none of these want the event, then the component
	* walks though it's parents looked for actions of type WHEN_ANCESTOR_OF_FOCUSED_COMPONENT.
	*
	* If no one has taken it yet, then it winds up here. We then look for components registered
	* for WHEN_IN_FOCUSED_WINDOW events and fire to them. Note that if none of those are found
	* then we pass the event to the menubars and let them have a crack at it. They're handled differently.
	*
	* Lastly, we check if we're looking at an internal frame. If we are and no one wanted the event
	* then we move up to the InternalFrame's creator and see if anyone wants the event (and so on and so on).
	*
	*
	* @see InputMap
	*/
	class KeyboardManager {

	static KeyboardManager currentManager = new KeyboardManager();

	/**
	* maps top-level containers to a sub-hashtable full of keystrokes
	*/
	Hashtable<Container, Hashtable> containerMap = new Hashtable<Container, Hashtable>();

	/**
	* Maps component/keystroke pairs to a topLevel container
	* This is mainly used for fast unregister operations
	*/
	Hashtable<ComponentKeyStrokePair, Container> componentKeyStrokeMap = new Hashtable<ComponentKeyStrokePair, Container>();

	public static KeyboardManager getCurrentManager() {
	return currentManager;
	}

	public static void setCurrentManager(KeyboardManager km) {
	currentManager = km;
	}

	/**
	* register keystrokes here which are for the WHEN_IN_FOCUSED_WINDOW
	* case.
	* Other types of keystrokes will be handled by walking the hierarchy
	* That simplifies some potentially hairy stuff.
	*/
	public void registerKeyStroke(KeyStroke k, JComponent c) {
	Container topContainer = getTopAncestor(c);
	if (topContainer == null) {
	return;
	}
	Hashtable keyMap = containerMap.get(topContainer);

	if (keyMap == null) { // lazy evaluate one
	keyMap = registerNewTopContainer(topContainer);
	}

	Object tmp = keyMap.get(k);
	if (tmp == null) {
	keyMap.put(k,c);
	} else if (tmp instanceof Vector) { // if there's a Vector there then add to it.
	Vector v = (Vector)tmp;
	if (!v.contains(c)) { // only add if this keystroke isn't registered for this component
	v.addElement(c);
	}
	} else if (tmp instanceof JComponent) {
	// if a JComponent is there then remove it and replace it with a vector
	// Then add the old compoennt and the new compoent to the vector
	// then insert the vector in the table
	if (tmp != c) { // this means this is already registered for this component, no need to dup
	Vector<JComponent> v = new Vector<JComponent>();
	v.addElement((JComponent) tmp);
	v.addElement(c);
	keyMap.put(k, v);
	}
	} else {
	System.out.println("Unexpected condition in registerKeyStroke");
	Thread.dumpStack();
	}

	componentKeyStrokeMap.put(new ComponentKeyStrokePair(c,k), topContainer);

	// Check for EmbeddedFrame case, they know how to process accelerators even
	// when focus is not in Java
	if (topContainer instanceof EmbeddedFrame) {
	((EmbeddedFrame)topContainer).registerAccelerator(k);
	}
	}

	/**
	* Find the top focusable Window, Applet, or InternalFrame
	*/
	private static Container getTopAncestor(JComponent c) {
	for(Container p = c.getParent(); p != null; p = p.getParent()) {
	if (p instanceof Window && ((Window)p).isFocusableWindow() \|\|
	p instanceof Applet \|\| p instanceof JInternalFrame) {

	return p;
	}
	}
	return null;
	}

	public void unregisterKeyStroke(KeyStroke ks, JComponent c) {

	// component may have already been removed from the hierarchy, we
	// need to look up the container using the componentKeyStrokeMap.

	ComponentKeyStrokePair ckp = new ComponentKeyStrokePair(c,ks);

	Container topContainer = componentKeyStrokeMap.get(ckp);

	if (topContainer == null) { // never heard of this pairing, so bail
	return;
	}

	Hashtable keyMap = containerMap.get(topContainer);
	if (keyMap == null) { // this should never happen, but I'm being safe
	Thread.dumpStack();
	return;
	}

	Object tmp = keyMap.get(ks);
	if (tmp == null) { // this should never happen, but I'm being safe
	Thread.dumpStack();
	return;
	}

	if (tmp instanceof JComponent && tmp == c) {
	keyMap.remove(ks); // remove the KeyStroke from the Map
	//System.out.println("removed a stroke" + ks);
	} else if (tmp instanceof Vector ) { // this means there is more than one component reg for this key
	Vector v = (Vector)tmp;
	v.removeElement(c);
	if ( v.isEmpty() ) {
	keyMap.remove(ks); // remove the KeyStroke from the Map
	//System.out.println("removed a ks vector");
	}
	}

	if ( keyMap.isEmpty() ) { // if no more bindings in this table
	containerMap.remove(topContainer); // remove table to enable GC
	//System.out.println("removed a container");
	}

	componentKeyStrokeMap.remove(ckp);

	// Check for EmbeddedFrame case, they know how to process accelerators even
	// when focus is not in Java
	if (topContainer instanceof EmbeddedFrame) {
	((EmbeddedFrame)topContainer).unregisterAccelerator(ks);
	}
	}

	/**
	* This method is called when the focused component (and none of
	* its ancestors) want the key event. This will look up the keystroke
	* to see if any chidren (or subchildren) of the specified container
	* want a crack at the event.
	* If one of them wants it, then it will "DO-THE-RIGHT-THING"
	*/
	public boolean fireKeyboardAction(KeyEvent e, boolean pressed, Container topAncestor) {

	if (e.isConsumed()) {
	System.out.println("Acquired pre-used event!");
	Thread.dumpStack();
	}

	// There may be two keystrokes associated with a low-level key event;
	// in this case a keystroke made of an extended key code has a priority.
	KeyStroke ks;
	KeyStroke ksE = null;


	if(e.getID() == KeyEvent.KEY_TYPED) {
	ks=KeyStroke.getKeyStroke(e.getKeyChar());
	} else {
	if(e.getKeyCode() != e.getExtendedKeyCode()) {
	ksE=KeyStroke.getKeyStroke(e.getExtendedKeyCode(), e.getModifiers(), !pressed);
	}
	ks=KeyStroke.getKeyStroke(e.getKeyCode(), e.getModifiers(), !pressed);
	}

	Hashtable keyMap = containerMap.get(topAncestor);
	if (keyMap != null) { // this container isn't registered, so bail

	Object tmp = null;
	// extended code has priority
	if( ksE != null ) {
	tmp = keyMap.get(ksE);
	if( tmp != null ) {
	ks = ksE;
	}
	}
	if( tmp == null ) {
	tmp = keyMap.get(ks);
	}

	if (tmp == null) {
	// don't do anything
	} else if ( tmp instanceof JComponent) {
	JComponent c = (JComponent)tmp;
	if ( c.isShowing() && c.isEnabled() ) { // only give it out if enabled and visible
	fireBinding(c, ks, e, pressed);
	}
	} else if ( tmp instanceof Vector) { //more than one comp registered for this
	Vector v = (Vector)tmp;
	// There is no well defined order for WHEN_IN_FOCUSED_WINDOW
	// bindings, but we give precedence to those bindings just
	// added. This is done so that JMenus WHEN_IN_FOCUSED_WINDOW
	// bindings are accessed before those of the JRootPane (they
	// both have a WHEN_IN_FOCUSED_WINDOW binding for enter).
	for (int counter = v.size() - 1; counter >= 0; counter--) {
	JComponent c = (JComponent)v.elementAt(counter);
	//System.out.println("Trying collision: " + c + " vector = "+ v.size());
	if ( c.isShowing() && c.isEnabled() ) { // don't want to give these out
	fireBinding(c, ks, e, pressed);
	if (e.isConsumed())
	return true;
	}
	}
	} else {
	System.out.println( "Unexpected condition in fireKeyboardAction " + tmp);
	// This means that tmp wasn't null, a JComponent, or a Vector. What is it?
	Thread.dumpStack();
	}
	}

	if (e.isConsumed()) {
	return true;
	}
	// if no one else handled it, then give the menus a crack
	// The're handled differently. The key is to let any JMenuBars
	// process the event
	if ( keyMap != null) {
	Vector v = (Vector)keyMap.get(JMenuBar.class);
	if (v != null) {
	Enumeration iter = v.elements();
	while (iter.hasMoreElements()) {
	JMenuBar mb = (JMenuBar)iter.nextElement();
	if ( mb.isShowing() && mb.isEnabled() ) { // don't want to give these out
	boolean extended = (ksE != null) && !ksE.equals(ks);
	if (extended) {
	fireBinding(mb, ksE, e, pressed);
	}
	if (!extended \|\| !e.isConsumed()) {
	fireBinding(mb, ks, e, pressed);
	}
	if (e.isConsumed()) {
	return true;
	}
	}
	}
	}
	}

	return e.isConsumed();
	}

	void fireBinding(JComponent c, KeyStroke ks, KeyEvent e, boolean pressed) {
	if (c.processKeyBinding(ks, e, JComponent.WHEN_IN_FOCUSED_WINDOW,
	pressed)) {
	e.consume();
	}
	}

	public void registerMenuBar(JMenuBar mb) {
	Container top = getTopAncestor(mb);
	if (top == null) {
	return;
	}
	Hashtable keyMap = containerMap.get(top);

	if (keyMap == null) { // lazy evaluate one
	keyMap = registerNewTopContainer(top);
	}
	// use the menubar class as the key
	Vector menuBars = (Vector)keyMap.get(JMenuBar.class);

	if (menuBars == null) { // if we don't have a list of menubars,
	// then make one.
	menuBars = new Vector();
	keyMap.put(JMenuBar.class, menuBars);
	}

	if (!menuBars.contains(mb)) {
	menuBars.addElement(mb);
	}
	}


	public void unregisterMenuBar(JMenuBar mb) {
	Container topContainer = getTopAncestor(mb);
	if (topContainer == null) {
	return;
	}
	Hashtable keyMap = containerMap.get(topContainer);
	if (keyMap!=null) {
	Vector v = (Vector)keyMap.get(JMenuBar.class);
	if (v != null) {
	v.removeElement(mb);
	if (v.isEmpty()) {
	keyMap.remove(JMenuBar.class);
	if (keyMap.isEmpty()) {
	// remove table to enable GC
	containerMap.remove(topContainer);
	}
	}
	}
	}
	}
	protected Hashtable registerNewTopContainer(Container topContainer) {
	Hashtable keyMap = new Hashtable();
	containerMap.put(topContainer, keyMap);
	return keyMap;
	}

	/**
	* This class is used to create keys for a hashtable
	* which looks up topContainers based on component, keystroke pairs
	* This is used to make unregistering KeyStrokes fast
	*/
	class ComponentKeyStrokePair {
	Object component;
	Object keyStroke;

	public ComponentKeyStrokePair(Object comp, Object key) {
	component = comp;
	keyStroke = key;
	}

	public boolean equals(Object o) {
	if ( !(o instanceof ComponentKeyStrokePair)) {
	return false;
	}
	ComponentKeyStrokePair ckp = (ComponentKeyStrokePair)o;
	return ((component.equals(ckp.component)) && (keyStroke.equals(ckp.keyStroke)));
	}

	public int hashCode() {
	return component.hashCode() * keyStroke.hashCode();
	}

	}

	} // end KeyboardManager

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