/*

 * Copyright (c) 2005, 2011, 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(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;

    }

}