META-INF.modules.java.desktop.classes.sun.awt.PaintEventDispatcher Maven / Gradle / Ivy
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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*/
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}.
*
* @param dispatcher PaintEventDispatcher
*/
public static void setPaintEventDispatcher(
PaintEventDispatcher dispatcher) {
synchronized(PaintEventDispatcher.class) {
PaintEventDispatcher.dispatcher = dispatcher;
}
}
/**
* Returns the currently active {@code PaintEventDispatcher}. 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} that should be
* dispatched for the specified component. If this returns null
* no {@code PaintEvent} is dispatched.
*
* WARNING: 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(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;
}
}