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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;

	import java.awt.event.MouseEvent;
	import java.awt.event.ActionEvent;
	import java.awt.event.WindowEvent;

	import java.util.ArrayList;
	import sun.util.logging.PlatformLogger;

	import sun.awt.dnd.SunDragSourceContextPeer;
	import sun.awt.EventQueueDelegate;

	/**
	* EventDispatchThread is a package-private AWT class which takes
	* events off the EventQueue and dispatches them to the appropriate
	* AWT components.
	*
	* The Thread starts a "permanent" event pump with a call to
	* pumpEvents(Conditional) in its run() method. Event handlers can choose to
	* block this event pump at any time, but should start a new pump (<b>not</b>
	* a new EventDispatchThread) by again calling pumpEvents(Conditional). This
	* secondary event pump will exit automatically as soon as the Condtional
	* evaluate()s to false and an additional Event is pumped and dispatched.
	*
	* @author Tom Ball
	* @author Amy Fowler
	* @author Fred Ecks
	* @author David Mendenhall
	*
	* @since 1.1
	*/
	class EventDispatchThread extends Thread {

	private static final PlatformLogger eventLog = PlatformLogger.getLogger("java.awt.event.EventDispatchThread");

	private EventQueue theQueue;
	private volatile boolean doDispatch = true;

	private static final int ANY_EVENT = -1;

	private ArrayList<EventFilter> eventFilters = new ArrayList<EventFilter>();

	EventDispatchThread(ThreadGroup group, String name, EventQueue queue) {
	super(group, name);
	setEventQueue(queue);
	}

	/*
	* Must be called on EDT only, that's why no synchronization
	*/
	public void stopDispatching() {
	doDispatch = false;
	}

	public void run() {
	try {
	pumpEvents(new Conditional() {
	public boolean evaluate() {
	return true;
	}
	});
	} finally {
	getEventQueue().detachDispatchThread(this);
	}
	}

	void pumpEvents(Conditional cond) {
	pumpEvents(ANY_EVENT, cond);
	}

	void pumpEventsForHierarchy(Conditional cond, Component modalComponent) {
	pumpEventsForHierarchy(ANY_EVENT, cond, modalComponent);
	}

	void pumpEvents(int id, Conditional cond) {
	pumpEventsForHierarchy(id, cond, null);
	}

	void pumpEventsForHierarchy(int id, Conditional cond, Component modalComponent) {
	pumpEventsForFilter(id, cond, new HierarchyEventFilter(modalComponent));
	}

	void pumpEventsForFilter(Conditional cond, EventFilter filter) {
	pumpEventsForFilter(ANY_EVENT, cond, filter);
	}

	void pumpEventsForFilter(int id, Conditional cond, EventFilter filter) {
	addEventFilter(filter);
	doDispatch = true;
	while (doDispatch && !isInterrupted() && cond.evaluate()) {
	pumpOneEventForFilters(id);
	}
	removeEventFilter(filter);
	}

	void addEventFilter(EventFilter filter) {
	if (eventLog.isLoggable(PlatformLogger.Level.FINEST)) {
	eventLog.finest("adding the event filter: " + filter);
	}
	synchronized (eventFilters) {
	if (!eventFilters.contains(filter)) {
	if (filter instanceof ModalEventFilter) {
	ModalEventFilter newFilter = (ModalEventFilter)filter;
	int k = 0;
	for (k = 0; k < eventFilters.size(); k++) {
	EventFilter f = eventFilters.get(k);
	if (f instanceof ModalEventFilter) {
	ModalEventFilter cf = (ModalEventFilter)f;
	if (cf.compareTo(newFilter) > 0) {
	break;
	}
	}
	}
	eventFilters.add(k, filter);
	} else {
	eventFilters.add(filter);
	}
	}
	}
	}

	void removeEventFilter(EventFilter filter) {
	if (eventLog.isLoggable(PlatformLogger.Level.FINEST)) {
	eventLog.finest("removing the event filter: " + filter);
	}
	synchronized (eventFilters) {
	eventFilters.remove(filter);
	}
	}

	boolean filterAndCheckEvent(AWTEvent event) {
	boolean eventOK = true;
	synchronized (eventFilters) {
	for (int i = eventFilters.size() - 1; i >= 0; i--) {
	EventFilter f = eventFilters.get(i);
	EventFilter.FilterAction accept = f.acceptEvent(event);
	if (accept == EventFilter.FilterAction.REJECT) {
	eventOK = false;
	break;
	} else if (accept == EventFilter.FilterAction.ACCEPT_IMMEDIATELY) {
	break;
	}
	}
	}
	return eventOK && SunDragSourceContextPeer.checkEvent(event);
	}

	void pumpOneEventForFilters(int id) {
	AWTEvent event = null;
	boolean eventOK = false;
	try {
	EventQueue eq = null;
	EventQueueDelegate.Delegate delegate = null;
	do {
	// EventQueue may change during the dispatching
	eq = getEventQueue();
	delegate = EventQueueDelegate.getDelegate();

	if (delegate != null && id == ANY_EVENT) {
	event = delegate.getNextEvent(eq);
	} else {
	event = (id == ANY_EVENT) ? eq.getNextEvent() : eq.getNextEvent(id);
	}

	eventOK = filterAndCheckEvent(event);
	if (!eventOK) {
	event.consume();
	}
	}
	while (eventOK == false);

	if (eventLog.isLoggable(PlatformLogger.Level.FINEST)) {
	eventLog.finest("Dispatching: " + event);
	}

	Object handle = null;
	if (delegate != null) {
	handle = delegate.beforeDispatch(event);
	}
	eq.dispatchEvent(event);
	if (delegate != null) {
	delegate.afterDispatch(event, handle);
	}
	}
	catch (ThreadDeath death) {
	doDispatch = false;
	throw death;
	}
	catch (InterruptedException interruptedException) {
	doDispatch = false; // AppContext.dispose() interrupts all
	// Threads in the AppContext
	}
	catch (Throwable e) {
	processException(e);
	}
	}

	private void processException(Throwable e) {
	if (eventLog.isLoggable(PlatformLogger.Level.FINE)) {
	eventLog.fine("Processing exception: " + e);
	}
	getUncaughtExceptionHandler().uncaughtException(this, e);
	}

	public synchronized EventQueue getEventQueue() {
	return theQueue;
	}
	public synchronized void setEventQueue(EventQueue eq) {
	theQueue = eq;
	}

	private static class HierarchyEventFilter implements EventFilter {
	private Component modalComponent;
	public HierarchyEventFilter(Component modalComponent) {
	this.modalComponent = modalComponent;
	}
	public FilterAction acceptEvent(AWTEvent event) {
	if (modalComponent != null) {
	int eventID = event.getID();
	boolean mouseEvent = (eventID >= MouseEvent.MOUSE_FIRST) &&
	(eventID <= MouseEvent.MOUSE_LAST);
	boolean actionEvent = (eventID >= ActionEvent.ACTION_FIRST) &&
	(eventID <= ActionEvent.ACTION_LAST);
	boolean windowClosingEvent = (eventID == WindowEvent.WINDOW_CLOSING);
	/*
	* filter out MouseEvent and ActionEvent that's outside
	* the modalComponent hierarchy.
	* KeyEvent is handled by using enqueueKeyEvent
	* in Dialog.show
	*/
	if (Component.isInstanceOf(modalComponent, "javax.swing.JInternalFrame")) {
	/*
	* Modal internal frames are handled separately. If event is
	* for some component from another heavyweight than modalComp,
	* it is accepted. If heavyweight is the same - we still accept
	* event and perform further filtering in LightweightDispatcher
	*/
	return windowClosingEvent ? FilterAction.REJECT : FilterAction.ACCEPT;
	}
	if (mouseEvent \|\| actionEvent \|\| windowClosingEvent) {
	Object o = event.getSource();
	if (o instanceof sun.awt.ModalExclude) {
	// Exclude this object from modality and
	// continue to pump it's events.
	return FilterAction.ACCEPT;
	} else if (o instanceof Component) {
	Component c = (Component) o;
	// 5.0u3 modal exclusion
	boolean modalExcluded = false;
	if (modalComponent instanceof Container) {
	while (c != modalComponent && c != null) {
	if ((c instanceof Window) &&
	(sun.awt.SunToolkit.isModalExcluded((Window)c))) {
	// Exclude this window and all its children from
	// modality and continue to pump it's events.
	modalExcluded = true;
	break;
	}
	c = c.getParent();
	}
	}
	if (!modalExcluded && (c != modalComponent)) {
	return FilterAction.REJECT;
	}
	}
	}
	}
	return FilterAction.ACCEPT;
	}
	}
	}

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