/*
* Copyright (c) 2005, 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 sun.awt;
import java.awt.Component;
import java.awt.Rectangle;
import java.awt.event.PaintEvent;
/**
* PaintEventDispatcher is responsible for dispatching PaintEvents. There
* can be only one PaintEventDispatcher active at a particular time.
*
*/
public class PaintEventDispatcher {
/**
* Singleton dispatcher.
*/
private static PaintEventDispatcher dispatcher;
/**
* Sets the current <code>PaintEventDispatcher</code>.
*
* @param dispatcher PaintEventDispatcher
*/
public static void setPaintEventDispatcher(
PaintEventDispatcher dispatcher) {
synchronized(PaintEventDispatcher.class) {
PaintEventDispatcher.dispatcher = dispatcher;
}
}
/**
* Returns the currently active <code>PaintEventDispatcher</code>. This
* will never return null.
*
* @return PaintEventDispatcher
*/
public static PaintEventDispatcher getPaintEventDispatcher() {
synchronized(PaintEventDispatcher.class) {
if (dispatcher == null) {
dispatcher = new PaintEventDispatcher();
}
return dispatcher;
}
}
/**
* Creates and returns the <code>PaintEvent</code> that should be
* dispatched for the specified component. If this returns null
* no <code>PaintEvent</code> is dispatched.
* <p>
* <b>WARNING:</b> This is invoked from the native thread, be careful
* what methods you end up invoking here.
*/
public PaintEvent createPaintEvent(Component target, int x, int y, int w,
int h) {
return new PaintEvent((Component)target, PaintEvent.PAINT,
new Rectangle(x, y, w, h));
}
/**
* Returns true if a native background erase should be done for
* the specified Component.
*/
public boolean shouldDoNativeBackgroundErase(Component c) {
return true;
}
/**
* This method is invoked from the toolkit thread when the surface
* data of the component needs to be replaced. The method run() of
* the Runnable argument performs surface data replacing, run()
* should be invoked on the EDT of this component's AppContext.
* Returns true if the Runnable has been enqueued to be invoked
* on the EDT.
* (Fix 6255371.)
*/
public boolean queueSurfaceDataReplacing(Component c, Runnable r) {
return false;
}
}